It's slower than normal on most of the page, but if you scroll all the way down to the bottom of the page, when the page footer starts becoming visible the framerates drop drastically. Try it.
For what it's worth, the same site in IE7 exhibits no noticeable slowdown.
I am actually seeing the same behavior on Windows XP, Firefox 3.0 RC2. So this is not a problem isolated to Linux.
The best example I have seen of the problem is on this site: http:// www.timothysyke s.com/
It's slower than normal on most of the page, but if you scroll all the way down to the bottom of the page, when the page footer starts becoming visible the framerates drop drastically. Try it.
For what it's worth, the same site in IE7 exhibits no noticeable slowdown.