BlazBlue's pretty impressive visually and looks exactly like the console versions. Nice to have a portable version of the game that doesn't look like ass. I got online and found some matches much faster than UMvC3, but they were much, much laggier. Surprising coming from Arc, but will try again later.
The Gravity Daze demo is very, very short. You run around attack/jump with square/triangle, then use R to lift yourself off the ground. You can aim yourself using either the R stick or by moving the Vita around. L will put you back on the ground. When enemies appear, you can lose gravity and go up, then hurl yourself down onto them for massive damage. A Dragonball Z game made using this engine would be awesome, I think; I got that kind of feeling during the one lone action sequence the demo offers. Cinematics are done in a mix of still comic book style panels and FMVs. The characters seem to be speaking a made-up language.
Also when I tried plugging my Vita into my PC, I suddenly was unable to turn the system on. It wasn't dead; the PS button starting pulsating purple. Wasn't able to turn it back on until I plugged into an outlet and held down the power button for about 30 seconds. Weird.