Google has lost the guy who started and led its Chrome OS project to Facebook.

Matthew Papakipos (pictured), who joined Google in 2007 when it acquired PeakStream which he founded, tweeted the news Monday morning, saying “Now that Chrome OS & WebGL are in good shape, it’s time for something new. I’m going to work @ Facebook! Love the product and team. Woot!”

Google, meanwhile, is running up a Facebook clone according to a tweet Saturday by Digg co-founder and CEO Kevin Rose that said, “Ok, umm, huge rumor: Google to launch Facebook competitor very soon ‘Google Me,’ very credible source.”

Rose’s tweet led to speculation that Google could be combining Orkut and Buzz or doing some kind of takeover off on Google Profiles.

Google’s got to be worried about where its traffic is going these days. Facebook is now supposed to have 450 million members, going on 500 million and according to the New York Daily News it did $800 million last year.

For its part Facebook has also hired VMware’s Desktop Business Unit boss Jocelynn Goldfein. As what is unclear.

Papakipos didn’t say what he was going to Facebook as either and Facebook isn’t telling. Facebook recently picked up senior Android developer Eric Tseng to run mobile products.

According to Papakipos’ online resume, he ran the Chrome UI team, managed Chrome’s HTML 5 APIs as well as its GPU-accelerated 3D APIs and started Google’s NativeClient project, its Native C++ code for web apps. Before PeakStream, he was director of architecture at Nvidia and before that a member of the technical staff at SGI. He holds some 45 patents with another 30 pending. He sees himself as a complex computer systems architect and entrepreneur.