I'll take a crack at this one. You are into a couple rules of thumb here.
1) Exposure is now considered a triangle: Shutter speed, Aperature, and ISO. Digital has made the third one, ISO, as easy to change as the other two. The XT will give you very usable speeds up to ISO 800 and beyond.
2) If the television media are there, use their lights which I have found to be very close to daylight but certainly within adjustable limits if you shoot RAW.
3) Remember another rule of thumb which is to keep your shutter speed at least equal to your focal length. i.e. 200mm - 1/250sec or faster.
4) Use tripod or monopod - monopod much easier in the anticipated crowds.
I hope this helps a little bit, and is the kind of info you were looking for.
Bill in WV