I'm basing it on 30 seconds of video I saw in the BK video. It doesn't look any different than Madden 06 except for the graphics. Not much to go on, I admit. I believe it's going to be an enhanced port. I won't be convinced until someone shows me different.
The passing game could be changed in different ways. Chad Pennington soft arm, for example. Not just not being able to throw far, but floating even ten yard passes. The ability to throw to an (in)eligible receiver while being tackled. Kinda like a dump off desparation toss to a linemen. More realistic pass blocking. There are many things that can be tweaked with the physics and the logic to allow for a more realistic, yet more entertaining and unpredictable game.
I understand the difference between a game engine and a graphics engine. I expect a totally new graphics engine with the next generation game, too. Looking at the video, the one thing that stood out to me was the grass. It looks like crap still. I would think with the power of the PS3 and the 360, EA could show individual blades of grass on the field. Just throw some shine on the RealTurf fields (everybody's got them now, right?).
These are things I expect to see in Madden 07 next year.
Yes, I think Madden 360 is going to be a port, but, no, I'm not going to argue about it. I have no proof either way. I don't have any conspiracy theories, and I'm not going to accuse EA of being lazy or anything of the like. Just a personal opinion until I see different. I'm not going to be disappointed in Madden 360, either. It should be a great game.