Go Nintendo has a recent post about some information found in IGN Insider's Gaming Life in Japan feature, which contains information from Nintendo Dream, a Japanese gaming publication. Nintendo Dream interviews NoJ spokesperson Mitsuaki Hagishima about the 'cube and the rest of its lifespan. Here's an excerpt:

5. Nintendo isn't done with the GameCube software announcements just yet! GameCube will be getting more titles, including some sequels to series that are well known. Hagishima states that one of the titles in development will surprise people with the new kind of gameplay it achieves on the GameCube. He claims to have actually played the game and promises that it will be announced soon.

Sequels to well-known series?! If anything, I bet that will be a Mario Party sequel, perhaps with new camera integration. Either way, keep your ears open (especially with E3 right around the corner).