I've spent the day using IE8 and while it is faster, some pages have problems. If your seeing this, download this add-on to submit to Microsoft.
Report a Webpage Problem Internet Explorer 8.0 Beta Add-On
The Microsoft Report a Webpage Problem Internet Explorer Add-on allows the user to submit a report to Microsoft for webpages they believe are having rendering problems, scripting errors, or various other types of problems
Download details: Report a Webpage Problem Internet Explorer 8.0 Beta Add-On
To use, go to the tools menu and select Report a Webpage Problem
Then you get to submit a page like this:
Fri, Mar 7 2008 9:53 PM