Wow. Quite the response, thanks for the comments. I was the programmer/designer on the project. To answer a few questions..
On the Unicorn rainbows: Yeah that was the original plan, but it ended up cut since we ran out of time towards the end of the contest on account of having to fix some dire last minute issues with the 360 version. Similarly for the animations, we way underestimated the amount and the transitions required to get them right in time along with a bevy of issues with the physics engine in general. The whole thing was made in the last month of the contest.
To clarify the Unicorn mechanic since a few people were confused: You can spawn it in a direction at any time in certain areas as well as change its speed, but not its direction without respawning it. We did manage to smooth out the spawning of it at the last minute with a poof effect. If you check out the other video
you can see a few more of the mechanics related to it.
As for the release, yeah it's pretty much going to be restricted to Microsoft's creator club shenanigans for the time being depending on how the contest goes. Given the awkwardness of keyboard controls in the game and the nightmare we had getting testers to have XNA to run on their computers without installing the entire SDK, I wouldn't count on much else anytime soon.