As an aside, did you work on the indexing team at Google? I was on the indexing team from 2005-2007, and I remember that Javascript execution was being worked on then, but I don't remember who was doing it (was a long time ago ;) ). My name is my username.
I was always in the New York office (before and after the move from Times Square to Chelsea), on the Rich Content Team sub-team of Indexing. My username is the same as my old Google username.
I was working on the lightweight high-performance JavaScript interpretation system that sandboxed pretty much just a JS engine and a DOM implementation that we could run on every web page on the index. Most of my work was trying to improve the fidelity of the system. My code analyzed every web page in the index.
Towards the end of my time there, there was someone in Mountain View working on a heavier, higher-fidelity system that sandboxed much more of a browser, and they were trying to improve performance so they could use it on a higher percentage of the index.