Reported by WiiNintendo.net, we've heard that the new Mii channel will including new things to do with your Mii's such as voting on other peoples Mii's and no doubt some kinda Celeb Mii area.
"During the Nintendo keynote Shigeru Miyamoto mentioned that a new voting channel where people can vote on their favorite Miis was in the works. A message was sent to Japanese Wiis with the date of the new channel, April 29. In the channel players can pick one of two Miis as their favorite and results will be shown online, similar to the Everybody Votes channel."
We'll let you know when its coming to the US, EU soon!