It looked pretty janky to me, severely unpolished. Mind you, I never played the first Dead Rising and this was only one level. From a pure gameplay standpoint it looked fun but the sluggish framerate killed any appeal for me. I'm talking like 15 FPS. Literally looked like the game was running in slow-mo. Animation appeared choppy as a result. Felt like throwing up.
I still was willing to give it a try but there was someone else playing it at the time, so it was either wait for 20-30 minutes or go try something else on the show floor. I chose the latter.
I realize it is a prerelease version but the full game releases in what, 3 months? So I think criticism on performance are valid at this point. It's more like 2 months when you factor in production time.
Without a video I'd agree this article is borderline pointless. That's why I refrained from posting anything on it.
For what it's worth, the framerate should be a non-issue in the PC version, assuming you have a good enough rig.