MCV that versions of Ben 10: Protector of Earth for Wii, DS, PSP and PS2 have sold a collective 2.5 million copies worldwide. While not nearly as impressive as Gears of War 2's feat of selling 2 million in one week, we suspect the cost of development for Ben 10: PoE was quite a bit less (and D3's metric perhaps a bit lower). The title has been in the Top 40 UK software sales consistently since launching October 2007.
This bravado is not without apt timing, of course, as the publisher is gearing up for the release of Ben 10: Alien Force in February. Expect mediocre reviews for the game and a hefty profit margin for D3 -- behold the power of a licensed IP.