I'm playing the Chromehounds demo for the Xbox 360.
This is next-gen(ish) mech game, kind of sim-ish in tone, and pretty fun.
The demo consists of two brief single-player levels -- "search and destroy" and "sniping".
The demo has no customizing of the mechs (called "Hounds" in the game), but the game play is pretty solid, if not totally next-gen. Lots of things are destructable (from light posts to trees to buildings), but they're canned -- they always collapse the same way after a set number of hits, depending on the objects (kind of like a less-pretty version of Halo 2's warhog demolition).
Actually, the physics in general could use some work. For example, pounding away with big shells at the ground near on-foot soldiers has no effect -- you've got to physically hit them to make a difference. Also, I'm really waiting for a next-gen mech game where falling down a mountain looks and feels "real" -- think the scene in Return of the Jedi where the AT-ST (scout walker) is tumbling about on Ewok logs, before wiping out and exploding.
On the plus side, there is some nice attention to detail, like when I fell down said mountain, I damaged my hydraulics, which caused some stilted movement and sparking, and this was carried over into the ending cut-scene in the sniper level. And the voice acting doesn't totally suck
Also, the brief bits of music are really pretty amazing.
Overall, this game feels to me be a mix somewhere between the phenomenal Heavy Gear PC series and Microsoft's own (excellent) MechAssault II: Lone Wolf.
I'm thinking multiplayer is going to be where it's at with this game -- and it'll be the only new game in town for the summer Xbox 360 mutliplayer front (unless 3D Realms totally fixes Prey's mutliplayer pain fest).