
You're guaranteed of plenty of power, more than enough. They all have it in abundance.
THD figures are all healthy these days. Crossover distortion is the biggest issue with solid state, but that's just something we live with until tube receivers are all the rage (heh-heh).
They all have enough channels. Only entry level receivers or oddball models don't have 7.1
HDMI is the input of choice these days. DVD, BluRay, HD set-top boxes all have them. But there are always other digital and analog inputs to play with should you have older gear.
All have the must have features. You just have to decide if you need anything the receiver doesn't have (unlikely).
Keep it simple and get one of these (link):
Don't worry about lack of 1080p precessing. If you have a 1080p TV it'll do it for you. If you don't it doesn't matter.
Sig' begineth here: