Pfui - 9:52 am on Nov 25, 2010 (gmt 0)

Ironically, a related document with a 2010 (c) date listing their "crawlers" is conflicting...

FYI
Appendix: Google's website crawlers [code.google.com]

NEW (?)
Googlebot-News (née Feedfetcher?)
Googlebot-Video
(also)
"Google also uses some other user-agents, not listed here, to fetch content in real time in response to a user's action." (That sounds like the troublesome new Google Web Preview [webmasterworld.com]...)

AWOL
(in no particular order)
Feedfetcher-Google; (+http://www.google.com/feedfetcher.html; [...etc.]
Google Web Preview
Google Wireless Transcoder
Google Keyword Generator
Google-Site-Verification
AppEngine-Google spawn
Any UA... "(via translate.google.com)"
NO UA

FWIW
The Appendix is referenced in G's robots.txt docs rehash and refers to G's listed agents as "crawlers." That could be a doublespeakish way of saying the list-AWOL UAs ignore robots.txt. Because they do.