Our affiliates over at GameCubicle reported that there might be a new Pokemon game heading towards the GameCube. Here is their news tidbit:

ESRB, the nation's leading entertainment software rating body, has given the first indication as to the existence of a new GameCube game from Nintendo titled 'Pichu Bros: Party Panic'. Though no further details are currently known, it can be speculated that the game will feature Pichu, Pokemon #172, or the pre-evolution of Pikachu. The "Party Panic" title may also suggest gameplay similar to that seen in Mario Party. Firm details on the game should be revealed at May's E3 Expo.

Source: GameCubicle