Trying out Firefox 4

> unlike 3.5 which seems plagued by some kind of hang that happens more-or-less daily. I've always suspected Flash as the culprit, but never narrowed it down to that for sure.

Flashblock is your friend: a dead-simple interface to cherry-pick only the Flash you want. https://addons.mozilla.org/en-US/firefox/addon/433/

(downloaded more than 8 million times already)