The Yamaha RX-V757 is identical to the 750, which is what I have, except for the presence of XM Radio in the newer 757. I can say without hesitation, that I absolutely love my 750. Bear in mind, I have a small room (~300 square feet) and not too many components to hook up. So for me, the 750 was and still is perfect for me. The sound of both movies and music is stellar. Sure, there are times when I read about the RX-V2600 or something, and get a pang of jealousy, but the truth is I don't regret the purchase of my 750 one bit.
And everyone else is right: you don't need to have the same brand for both receiver and DVD player.
cheers,
supervij