A former Microsoft employee who left to start his own company that was acquired by Google, left Google to go back to Microsoft. His opinions on the Google environment can be found in this online post.
It was an interesting read, primarily because I have heard so many good things about working at Google and while this does point out that most of that “good stuff” is true, it comes with some strings. That is just life though, some of the perks are fairly cool. Either way, it is a good read.