I usually use Chrome just for casual message board surfing because it's fast. I'll go to Firefox for shopping sites or if I need more features.
I actually like IE8 but never use it anymore because mine is broken and I haven't been able to troubleshoot it. It can't open a hotlink in a new tab - it opens the tab then just times out without loading the new page. IE8 still has the best bookmark management of any of the browsers, and the best implementation of tabs.