Just played about a half hour of the trial, and I'm loving it. I can see how it'd eventually get dull, but I don't really plan on playing this for hours on end. Just enough to make use of the 800 point pricetag and have some fun.
For those of you that want to check out the comp. version first, know that it's probably going to be very different from the XBLA one, unless there are extra features that aren't in trial mode.
Nice game though, probably going to be a rather easy 200.