Firefox 4 also crashing due to outdated graphics drivers
Please update your graphics drivers.
Like Google, Mozilla has noticed higher volumes of crash reports from Firefox 4 users who were running stale drivers. In addition to offering a general reminder to update your drivers, Mozilla has also posted a listing of the video card drivers which have been added to the Firefox 4 blocklist. If your driver is listed, it's imperative you update if you want to get the best performance out of Firefox 4.