The LocoRocos are coming back for another adventure on the PSP via the downloadable title, LocoRoco Midnight Carnival. Sony has recently released a trailer for the game that shows off the new Boing! super bounce feature.
No word yet on how you can split the LocoRocos up without the Circle button, but apparently a demo's in the works. The multiplayer mode has also been revealed to feature simultaneous play for up to four players. You can choose to go co-op or competitive.