claus - 11:58 pm on Feb 25, 2010 (gmt 0)
IMHO, 2 seconds is a bit slow. My fastest site runs around 0.6 seconds per page, including scripts, AS text-ads, and stylesheets. And that is a fetch from another continent (From EU to US). But then, for that site speed has always been a high priority.
However, the Adsense weight (32.7 KB) is twice that of the HTML of the page (14 KB), which is a real page with real informative text-based content. My page speed could have been 0.2 seconds witout AdSense, so it's a weight increase by 300%
The amount of text displayed in the AdSense ads is less than 5% of the text on the page, possibly as little as 1%!
So, whatever AdSense is, it's certainly not built for speed. AdSense is s-l-o-w.