For a Web site, it could hardly look less exciting. Its pages are heavy with text, much of it a flat blue, and there are few photos and absolutely no videos.

But LinkedIn, the social network for professionals, is dull by design. Unlike Facebook and MySpace, the site is aimed at career-minded, white-collar workers, people who join more for the networking than the social.

Now, in the midst of Silicon Valley’s recession-proof enthusiasm for community-oriented Web sites, the most boring of the social networks is finally grabbing the spotlight.

On Wednesday, LinkedIn will announce that it has raised $53 million in capital, primarily from Bain Capital Ventures, a Boston-based private equity firm. The new financing round values the company at $1 billion. That heady valuation is more than the $580 million that the News Corporation paid for MySpace in 2005, but less than the $15 billion value assigned to Facebook last year when Microsoft bought a minority stake.

LinkedIn’s investment round delays a rumored initial public offering, which would have finally tested the public market’s interest in social networking.

“What we didn’t want is to have the distraction of being public and to be worried by quarterly performance,” said Dan Nye, the buttoned-down chief executive of LinkedIn, who would not be caught dead in the Birkenstocks and rumpled T-shirts favored by MySpace and Facebook employees.

LinkedIn, which says it is already profitable, will use the investment to make acquisitions and expand its overseas operations.

“We want to create a broad and critical business tool that is used by tens of millions of business professionals every day to make them better at what they do,” Mr. Nye said.

The average age of a LinkedIn user is 41, the point in life where people are less likely to build their digital identities around dates, parties and photos of revelry.

LinkedIn gives professionals, even the most hopeless wallflower, a painless way to follow the advice of every career counselor: build a network. Users maintain online résumés, establish links with colleagues and business acquaintances and then expand their networks to the contacts of their contacts. The service also helps them search for experts who can help them solve daily business problems.

The four-year-old site is decidedly antisocial: only last fall, after what executives describe as a year of intense debate, did the company ask members to add photos to their profiles.

That business-only-please strategy appears to be paying off. The number of people using LinkedIn, based in Mountain View, Calif., tripled in May over the previous year, according to Nielsen Online. At 23 million members, LinkedIn remains far smaller than Facebook and MySpace, each with 115 million members, but it is growing considerably faster.

LinkedIn also has a more diversified approach to making money than its entertainment-oriented rivals, which are struggling to bring in ad dollars and keep up with inflated expectations for increased revenue.

LinkedIn will get only a quarter of its projected $100 million in revenue this year from ads. (It places ads from companies like Microsoft and Southwest Airlines on profile pages.) Other moneymakers include premium subscriptions, which let users directly contact any user on the site instead of requiring an introduction from another member.

A third source of revenue is recruitment tools that companies can use to find people who may not even be actively looking for new jobs. Companies pay to search for candidates with specific skills, and each day, they get new prospects as people who fit their criteria join LinkedIn.

LinkedIn is set to undergo a radical shift in strategy to find other sources of revenue. Instead of catering primarily to individual white-collar workers, the site will soon introduce new services aimed at companies. It is a risky move that could alienate members who prefer to use the networking site to network — without their bosses peering over their shoulders.

One new product, Company Groups, automatically gathers all the employees from a company who use LinkedIn into a single, private Web forum. Employees can pose questions to each other, and share and discuss news articles about their industry.

Soon, LinkedIn plans to add additional features, like a group calendar, and let independent developers contribute their own programs that will allow employees to collaborate on projects.

The idea is to let firms exploit their employees’ social connections, institutional memories and special skills — knowledge that large, geographically dispersed companies often have a difficult time obtaining.

While companies are interested in the business benefits of social networks such as Facebook, they also worry about their possible downsides, as I blogged back in January.

An alternative that makes sense to a growing number of companies, including Wachovia, is creating internal social networks for their employees. Among the features planned for Wachovia’s network, according to a CIO Insight article, are employee-authored blogs, wikis and an internal encyclopedia (Wachopedia?). Unlike turning workers loose on Facebook, an internal network makes it less likely they will expose sensitive company information to outsiders or spend hours taking movie quizzes and “poking” colleagues.

If you’re part of my generation, online social networking is a part of life. When you meet someone at a party and you hit it off, you ask if they’re on Facebook. If you meet a band, they’ll likely give you their Myspace Web address. Your photos are probably on Flickr for your friends and family to see. Maybe you have a blog or Web journal to update the world on your life.

Now there is an online community for those who are trying to better their financial situation: Debtsy.com, a new Web site I read about on WalletPop. “Debtsy is a place where you can connect with others as you eliminate debt and build wealth,” the site’s tagline says.

On the site, you can blog about your money situation, track your net worth, learn to invest and join a network of people who have the same goals. The site also has many different groups you can join and participate in, ranging from students working to pay off education loans and credit card debt to wannabe investors trying to learn the tricks of the trade. You also have the ability to control who sees your information, which is vital in online communities.

Your location on a friend network, a photo on Facebook, a prayer for a deployed family member on a military-based blog – all posted on the World Wide Web with the intent to bring comfort to loved ones and news to friends. This information may seem harmless, but when put together these puzzle pieces show a picture with more information than military members should share.

Col. Andy Pears, director of Communications and Information for Headquarters Air University, became a “completely fictional” staff sergeant on a social networking site designed for military members to demonstrate the amount of information available. The “sergeant” said he had no trouble creating a profile and false identity.

With a few mouse clicks, Colonel Pears found combat and operations histories, pictures from inside deployed locations, descriptions and duties within that location and details about military members receiving medals. There is never an attempt to confirm military affiliation, he said.

Last.fm (www.last.fm) today announced that it is launching a service to allow anyone to listen to music on the site for free.

Last.fm has become one of the leading places in the world where people can go to listen to music online. Its vast library has attracted a community of more than 20 million unique monthly users in 240 countries around the globe. The heart of Last.fm is a powerful recommendation engine that guides listeners to music they are likely to enjoy based on prior selections, connecting them with the music they love and with others who share their tastes.

In launching this service, Last.fm becomes the first music website to offer free, global, on-demand access to the largest licensed catalogue of music built on partnerships with all four major record labels - including Universal Music Group, Sony/BMG, Warner and EMI - as well as CD Baby, IODA, the Orchard, Naxos and more than 150,000 independent labels and artists.

Last.fm’s free-on-demand service will be advertiser supported, allowing clients many unique opportunities to reach a highly targeted and engaged audience.

Last.fm was acquired by the CBS Corporation on May 30, 2007.

“It is clear to us that communities built around great content are increasingly driving traffic and revenue online,” said Leslie Moonves, President and CEO of the CBS Corporation. “We acquired Last.fm because music is one of the best ways to build communities on the internet. Adding such a tremendous collection of content to Last.fm will help it grow by leaps and bounds. The skill set that we’re learning along the way will be very important as we build additional online communities around our other world-class content as well.”

Martin Stiksel, Last.fm co-founder, said: “We’re giving the listener free access to what is basically the best jukebox in the world. The ability to dip into such a uniquely broad catalogue from your laptop, home or office computer, and listen to whatever you want for free represents a new way of consuming music that in turn might change the way you listen to music. In that respect, nobody else can currently offer what Last.fm is offering right now.”