I don't know if this has been mentioned but DJ Max for the Vita is $39.99 for the U.S. version with free shipping. That's the lowest I've seen that game get.
That's tempting, but I might hold off for the PSN digital version to go on sale. I'm still on the fence with this one, seeing how I don't have a Vita at the moment. Not having a paper manual is also discouraging.