Few know that that P in Walter P. Mossberg's name stands for "Pokemon". He was the OG pocket monster battler for the WSJ back in the day. When choosing between the new, improved IE 7-point-oh, and the likewise fuh-fuh-fresh Firefox 2.0 Release Candidate 3, he choose one to be his winner: Firefox, for having everything IE 7 has, plus some new tricks.
In summary, IE just picked up some tabs, a search bar, and improved security...a short list in 2007 that Firefox 2.0 matches and exceeds, even before it's official release. FF adds spellcheking, a feature to recover your pages and tabs if the browser crashes, and lightning bolts it shoots out of its tail.
The only thing IE has that Walt likes is Quick Tabs, a way to see thumbnails of all tabs in one shot. Pretty cool, but like Apple's Zoom-Zoom Expose window feature.
Like most of the time, I agree with most of Walt says. This time, he leaves out the most notable and powerful feature of Firefox, and that is it's extensibility by open source hoodrats.
IE, nice. I still use Firefox 1.5 because new software is something to be feared.