Googlebot can implement jQuery...
Using a live-tracking system (which in turn uses ajax to retrieve and execute remote scripts using the jQuery library) I noticed today a visitor from Mountain View (unknown browser type). A quick check of the logs and it was, of course, the Googlebot, version 2.1, coming from 66.249.65.183.
Maybe it's been noted before, but I was quite surprised to see it executing such complex scripts, especially since the ajax isn't even triggered until half a second after page load.
Anyway, I thought it would be worth noting.