To me it seems Microsoft needs to take a leaf from Google's book and incorporate the automagical browser updating. IE, sadly, has always controlled the browser market because if comes prepackaged and most users are novice and oblivious to updating and system requirements. Sure people will say they are copying Google, but in doing this, they might finally be able to keep up with web standards as they are released instead of supporting new standards 2 years after everyone else does creating this entire version fiasco to begin with.
Google is only really able to do it because nobody is depending too much on stuff built on top of the browser (yet, anyway). When you've built whole internal apps on top of a browser, as many companies have built on IE, frequent upgrades that change anything can be problematic. Firefox is in an interesting in-between position, where they encourage frequent upgrades, but users who use a lot of add-ons are reluctant to upgrade too often, because upgrades often break add-ons.
Of course, it's not a problem if every upgrade is backwards-compatible with every add-on and intranet app, but that's tough to pull off.
