I upgraded to Firefox 2.0 almost immediately, but am feeling user's remorse. Perhaps 2.0 was a non-trivial improvement over 1.5, but the lack of familiarity with its options and preferences because things were changed (I'm sure there was a UI rationale) really means that I took a short-term step back. Anyway, this is my first irritation with Firefox, the "release" seemed timed to one-up IE 7.0, it really should have been a bug fix and the switcheroo in the UI seems to be the main reason to stick it with a 2.0, even though as I offer above I think the UI changes mean a loss of short term productivity.