Yesterday (April 28, 2009), Microsoft made Internet Explorer 8 (IE8) a critical update so if you're the kind of person who says install updates without looking, beware. I only mention this because currently there are a lot of sites that do not support IE8. In fact even the emulate IE7 mode doesn't render some sites like they do in IE7.

To avoid IE8 installing automatically, install the IE8 Blocker Toolkit from Microsoft, http://www.microsoft.com/downloads/details.aspx?FamilyID=21687628-5806-4ba6-9e4e-8e224ec6dd8c&displaylang=en .

If you have IE7 and wish to test IE8, or use IE6 too , I would recommend installing Virtual PC 2007.