As promised at last night's NY Web Standards meetup, this morning I tested to see if IE 8 would recognize IE 7 conditional comments when set to render in IE 7 standards mode. The unfortunate answer is no. You can review the test here: http://themechanism.com/barkode/demos-tutorials/ie8-version-targeting.php

Aside—I installed Safari 3.1 (525.13) on my PC (Windows Vista Home Premium Service Pack 1) this morning and, for the first time in months, it runs!