$15 billion?

Microsoft invests $240M in Facebook for exclusive advertising rights, putting a valuation of $15B on Facebook, which estimated $150M in revenues in 2007.

Facebook should send Google a thank-you card for driving up the price. The investment is, umm, interesting in light of Steve Ballmer’s comments last week. Was this a push from aQuantive?

Then again, it’s not like $240M less will be noticed in Redmond’s bank account.. a problem I’d like to have.