Web_speed - 2:21 am on Oct 8, 2008 (gmt 0)

or it might be one of Google's human evaluators looking at your site

I've been watching this thing in real time as it browse the site (was watching using an "who's online" type of script). The speed in which it browse pages was way too fast for humans (read: evaluators). At times, loading 2-4 pages p/second. Also, IP Reverse DNS shows "crawl-66-249-72-180.googlebot.com".

It behaved like a browser and fully invoked javascript (including javascript encrypted tracking code...as far as i know only browsers can do that). It was sending referrer information, occasionally starting with a google query page and advancing throughout the site.
Gobbled approx 200 pages in a 20 minutes frame....that's one hell of a dedicated speedy evaluator if you ask me. Nope...this thing was a bot. A very clever bot.

[edited by: Web_speed at 3:01 am (utc) on Oct. 8, 2008]