I have to use FF, IE, Safari and Chrome (because it's going to beat them all down the road, I'm sure) just to make sure designs and functions are cross-compatible, which is a pain.
But like I said, for clients and programs I have the bookmark list and am always in IE.
For popping to and from multiple sites for board posting, design checks, research, checking stats, twuffer and twitter posting, blogging, etc (multitasking), Chrome rocks for responsiveness and speed.
FF has a good SEO plug-in, and Safari, well.... sigh I'm not a Mac-fan but we still have to work on them, ya know?
