It's out on Xbox Live Arcade today. I downloded the free trial this morning about 10 minutes before leaving for work and played it for about 2 minutes, seems like it could be pretty fun. It feels a lot like Smash Brothers, and you get different types of projectile weapons with a primary and alternate fire, as well as some melee attacks. Projectiles are aimed with the right stick, so you can shoot in any direction. This looks good enough for me to spend 800 points on.