Hypocritical comments like this often seem to stem from one of two things: a desire to drum up needless press conflict or a complete lack of self-awareness. Perhaps Google has gotten the best of itself and in their all-consuming "must be, er, kill Facebook" dogma not realized that they are likely more a threat to privacy and openness as those they criticize.
The problem may essentially be that Brin is now too close to the whole situation to see the problem as it really is, that in his head what's right for Google and what's right for the internet are too closely linked.
Obviously there are two things here regardless of who you are - what you think is "good for" the internet and what you think is helping and hindering it. Brin's view is predicated on a particular view of the first point - what's good for the internet which is (for obvious reasons) very similar to Google's own view.
But any view on what's helping and what's hindering has to be viewed in terms of what you actually see as good for the internet.
https://twitter.com/#!/davewiner/status/191579280034103296