flash. *rawr*
This is slightly offtopic, but I would seriously suggest you reconsider doing EVERYTHING in flash. Will it look cool as anything? Quite possibly.
Unfortunately, the average person does not care about your brilliant animating talents. What they probably want is to just read your news, or find the calendar. That usually entails a site that loads quickly, without any real startup animations.
Imagine browsing to a page and being forced to wait 5 seconds before you can click any links (as things slowly animate in).
Animated headers, etc are fine. Just don't make your navigation or main site content display as flash. Please. Animation is nice, but inherently useless, and sometimes even pisses people off. (Some guy did a study and it seems that some people can't stand animation so much that they'll cover parts of their screen with their hand.)
End Anti-Flash auto rant.