Summary of the reviews:
* Fast and fun gameplay
* Solid controls
* Interesting motion-sensing implementation (Wii version)
* 32-player online is impressive
* Arcade mode is a fun diversion (Wii version).
* Story and mission structure bring nothing new to the table
* Longer than the last game, but still short (PSP version)
* Terrible AI.
Read Full Reviews links to the review of the Wii version. See the Alternative Sources below for the PSP review.