I voting for two channels only ... hehehe
I know that we are talking about "new" formats but I agree with tco. I have heard some of the new formats systems and although interesting, Im sticking with stereo for music only.
If your talking about HT, then maybe, but I will be dragging my feet as long as I can.

I have lived through vinyl, 8-track, cassette, CD. ( now its back to vinyl and CD)

VHS, Laserdisc and DVD. ( now its DVD on a decent HT setup using Carver electronics but nothing special) The format is Dolby Pro-logic and its just fine for me.

I love both listening to music and HT but IMHO, Its 2-separate systems for 2-separate mediums. The two will never be combined in my home if i can help it.