Ok, if you’ve read my previous post where I talk about IE8 rendering out of the box MOSS Master Pages poorly, you may have been confused by some of my results. Turns out I was using the Developer Tools to switch the Render Mode manually to IE8 which is not accurate. Turns out if a webpage does NOT include a doctype (like default.master and application.master do not) IE8 will default its rendering behavior to the old way of browsing (quirks mode in this case). Thus default.master and application.master, while still not great, do render exactly the same in IE8 as they would in IE7. Now BlueBand on the other hand (and the other “bands”) DOES have a doctype so it renders in IE8 mode by default and thusly has problems.
So, it would seem that the best case scenario for now with custom Master Pages, is to declare a doctype of your choice, but to include the new meta tag that forces IE7 rendering (since otherwise OOTB moss will have many problems). I for one, hope that the next service pack or version includes the appropriate back-end code to support full compliant mode.
P.s. Turns out you can always check your rendering mode quickly with this bookmarklet: http://www.enhanceie.com/ie/ie8.asp