This is free on Xbox Live's Games with Gold promotion right now.
In all honesty, it's a cute break from GTA V and GTA Online... and it /is/ pretty. Very pretty, and I'm a sucker for 2.5D! But this is pretty average, with questionable visual language for some of the traversal bits.
Story: As Sceneman pointed out, the writing is ABYSMAL. It is just short of being so-bad-it's-good, which is all the more sad, because it could have been just a shade more self-mocking. Actually, if they'd taken it even further and broken the 4th wall, it would have been even better for a 2.5D game! The inclusion of playable, '80s-era LCD games leads me to think that this was supposed to be a self-aware game with an intentionally ham-fisted story, but it lacks some punch.
Art: Another interesting choice are the comic-book style loading screens and story cinematics. The loading screens look like they might have been drawn by comic god Darwyn Cooke, but the animatic-style movies stray from that style into a shaggier, muddled look. It would be less of a problem to have two different illustration styles, except that neither one has ANY tie to the game's own illustration style. It's just odd to me that in this modern age, where making games look good seems to be the least difficult production problem to solve, that this inconsistency is present.
Gameplay: This feels pretty bog-standard, so far. I mean, I'm not seeing anything tricky in the problem solving area yet; the biggest issue is the control-scheme. Mainly, it's hard to deal with standing vertical jumps, for which the attach area appears laughably small. Doing jumping jacks while zombie hordes are clawing at you is the opposite of fun.