of course it's going to be limited testing. that keeps the buzz on it high because not everyone will have it (and the ones that DO have it will be talking about). so this way they can minimize the cost of doing it while still being able to fully test everything, and they'll still be getting some good publicity from it.
also, i liked halo 2. it wasn't quite as good as the first one, but it sure as hell didn't suck
this one looks really promising from everything i've seen, i think it's going to kick some serious ass