Movie tie-in games, what to say? However, Megamind: Ultimate Showdown happens to be one of the better ones I have played. While the game is clearly geared toward the younger generation of gamers, it actually is a pretty decent platformer. While the boss fights seem to get easier as the game goes on, it is constantly throwing achievements at you for simply playing the game. The only tricky achievements are the boss fight ones that require you to not die during the encounter, and even these are not that difficult. In fact, I managed to get through almost all of the last boss without taking ANY damage.
The game is relatively short (approximately 5 hours to complete the game), so it is definitely a rental over a purchase in my opinion. There is essentially no replay value (unless you have little ones) and there are several noticeable areas where the game could have used a little more polish. Overall I would rate this game as GOOD (borrowing from Stallion83's scale).