Mark Zuckerberg took to Facebook today to announce that Facebook has agreed to acquire photo-sharing service Instagram for $1 billion in "a combination of cash and shares of Facebook." The entire Instagram team — 6 13 employees — will be joining Facebook, and interestingly, Zuckerberg says that Instagram will be built and grown "independently" and that its integration with other services is an "important part of the experience." Over at the Instagram blog, CEO Kevin Systrom also announced that Instagram had agreed to be acquired, confirming that "you'll still be able to share to other social networks."

Notably, Zuckerberg also writes, "This is an important milestone for Facebook because it's the first time we've ever acquired a product and company with so many users. We don't plan on doing many more of these, if any at all." It's been quite a year for Instagram, with its recent launch of an Android app and growth to 30 million users, and this acquisition would put it up near the legendary Google buyout of $1.65 billion for YouTube in 2006.