snowshine-
Although there hasn't been an official timeframe announced for the availability of IE8 through Windows Update, it should be made available at some point. Folks who are using IE8 RC1 should be notified of the Windows Update availability prior to the rest of the public. If you can't wait for WU, a manual download will accomplish the same thing, though!
vistaFRUST, sorry you're having problems, I haven't seen that particular issue pop up yet. Have you tried taking a look at some of the forums at
Community Bookmarks - Microsoft TechNet? That's a fairly handy resource where you might be able to encounter other folks with similar issues. Let me know how it goes!
Thanks,
Cody
Internet Explorer Outreach Team