Launched in February 2004, Facebook is now worth $15BN - judging from the fact that Microsoft has reportedly just bought itself a modest 1.6% chunk of the company for a staggering $240M. Mark Zuckerberg, a former member of the Harvard Class of 2006, will not be short of change any time soon: as of October 2007, the website had 42 million active members worldwide and expects to pass 60 million users by the end of the year.

According to today's New York Times, "Microsoft will sell the banner ads appearing on Facebook outside of the United States, splitting the revenue with it."

"Making this investment and expanding this partnership will position Microsoft and Facebook to better take advantage of advertising opportunities around the world, and is a great win not only for our two companies, but also our collective users and advertisers," said Kevin Johnson, president of the Platforms & Services Division at Microsoft in a statement.

"We have partnered well over the past year and look forward to doing some exciting things together in the future. The opportunity to further collaborate as advertising partners is a big reason we have decided to take an equity stake, and is a strong statement of our confidence in the long-term economics of this partnership," Johnson added.

Zuckerberg's 20% stake in the company would now be worth $3BN and, despite the fact that MySpace has 110 million users, Facebook continues to be the poster child of the social networking movement. Almost 60 percent of Facebook's users are outside the U.S and currently an average of 200,000 new users register each day.

Last month the Wall Street Journal speculated that Microsoft's investment would be in return for a 5% stake, so the 1.6% figure suggests that Facebook perhaps drove a harder bargain than Redmond was expecting.

Google has yet to comment officially. 

AJAX plays its role at Facebook. Javeline for example released in July an AJAX application for Facebook using AJAX framework Javeline PlatForm and their Offline AJAX solution Javeline DeskRun. The Facebook application is called BeepMe and can be installed from http://beepme.javeline.com.

Whenever a friend is added, according to the team at Javeline, a mail is received or any of several other events a popup is displayed in the right bottom corner of the screen. The Facebook skin developed for this and upcoming applications will apparently be included in the next release of Javeline PlatForm.

• Zoho Puts SaaS Apps on Facebook
• Facebook Has Completely Replaced MySpace
• Y! Mash: Yahoo! Tries to Catch Up With Facebook
• SOA Secures Enterprise-Grade Social Networking
• Schroepfer Quits Mozilla, Joins Facebook as a Director of Engineering
• Behind the Scenes at Facebook: Scaling Up FBChat Using Erlang