Earth Defense Force has done pretty well on the PSP and PS3 in past iterations, and gets a revised outing on the Vita soon. A new video is out showing the EDF team fighting off some fricking-great alien monsters and mechs.
It does look a touch primitive but packs in the nasties and with four-player co-op should appeal to the Monster Hunter-deprived. It will launch in Japan in a normal, Limited Edition and a double-pack offering two copies. The Vita version comes with all the content in EDF3 plus new missions and monsters.