Great job
For all you reviewers who like multi-unit shooters like this, check out Shoot 1UP on XBLIG. It's a great game released a while ago with very similar gameplay to this game.
What I really like about this game is the control over formations and how that integrates into gameplay. However, I have one gripe. The system where as you change formation it pauses to show you info about it... that's unnecessary because you can already see what the formation is like when you do it! And since this is a twitchy shooter, having that pause is teeth-grindingly annoying when I want to quickly switch around to take something behind me or on the sides. The little icon can still pop up showing formation information, just maybe off to the side instead so as to not obscure view of the formation and let the formation itself come up instantly on your units.
Fix that one flow breaking 'pause' and the game mechanics will be perfect.