Heh, they seemed to have gotten a massive amount of media attention. I would've expected them to have met their goal a while ago.
I was one of the people who slipped in with a key a few weeks ago. The game is... interesting. It definitely lives up to its statement, and my first thought was that it was exactly what I wanted... then after playing a few rounds I realized I didn't actually understand what I wanted.
To explain:
The game is hardcore. Like, incredibly hardcore. If you're not actively researching openings, and strategies, and keeping up with the new releases and the meta, you're SOL. Completely. As much as they'd like to claim there's no "fixed opening book", that's only true in a technical sense. It's just that instead of having specific rules that apply all the time you have more basic rules like "if you're player 2 planning a heavy red start, do this", or "if you're player 1 hedging towards green, do this". These openings are then modified based on the specific cards in the set, with each card having a purpose (whether designed, or meta-assigned). Most of the meta discussion turns into best openings given the cards in the set/specific color focus or how to stop a specific strategy - both of which absolutely boil down to exact steps to take.
Couple this with the fact that the game is explicitly designed against having a come-back mechanism, and you find yourself basically walking a razor-edge throughout the game with you and your opponent competing to see who slips up first. Because once someone slips up, the game is basically over - there just might be a few rounds to go before this is apparent to one of both of the players.
The biggest place I see them going wrong is with the Starcraft comparison. No, Prismata is nothing like Starcraft. It's themed like Starcraft, sure, in that there's a beast-like resource, a mech-like resource, and a soldier-like resource, but the way the game actually plays, and should be understood as how it plays, is far more like chess-with-resources.
This isn't meant to scare people away from the game - it's definitely a very interesting, and well-designed, game. Just don't go in expecting "competitive Hearthstone" or "streamlined Starcraft". That's not what you're getting.
That all said, if you're still interested in playing (and these codes still work), here's three extra codes I was handed weeks ago. Help yourself (though they only work once, so note which one you use):
DGLGS-UAJQV-3HL92-6XB54LR7ZG-9S8HP-4MXKR-TKXWWEEWPK-G8W8C-9JFUH-96YZM
To use a key go to:
http://play.prismata.net/And press "Beta Key? Redeem it here"
EDIT/CAVEAT:
This is all based on games and forum discussions from about a month ago. That said, in that month it seems like their subreddit basically turned into "YAY/BOO Kickstarter!!" with no real in-depth discussion.