I personally think 38 billion is a fairly easy thing to shrink, when you bypass the entire middle-man in getting to facebook. If facebook adds search, and it's added into browsers, and homepages- why even go to Google?
No ad revenue = no 38 billion.
Apple is about to remove Google Maps from their platforms, and Bing is growing on Google everyday.
I personally have seen nothing of Google since Panda that has impressed me. Last thing I liked was Chrome's Browser. Panda while a successful algorithmic change, was poorly communicated to webmasters, and has pitted webmasters who helped build the giant into their enemy. I remember when Microsoft was the enemy of geeks, now for (some of) the web-savvy, it's Google. That drastic change in perception, filters into the public, and Google should have been more careful to preserve this relationship. In literature we would call this hubris. I would have suspected all the doctorate engineers over at Google to be smart enough, not to consider themselves immune from their own self-destruction.
Google+, is a nice product, but unfortunately no one likes it, and I resent the heck out Google for forcing webmasters into using rich snippets to rank by linking to Google+.