I think the bigger issue is the lens...you need a decent telephoto and none of the "pocket" digicams will give you that. And forget digital zoom...evil.
I've got a Panasonic Lumix DMC-FZ20PP. It is inbetween a small digicam and digital SLR sizewise, but has an honest -o-goodness 36-432mm optical lens on it that you can do autofocus or manual. It makes a big difference at the track. Most of these at LS were shot with it:
http://nostatic.com/photos/laguna05/
I still have a Canon SD400 that I try to carry everywhere (I've become an "art shot" addict), and a Nikon D70 that I actually don't use very often because I don't have the lenses i want for it yet...you need more than one camera
