GameHead interviewed Reggie at E3 and one of the things they talked about was the Wii Channels, and Reggie mentioned the Check Mii Out Channel. After that, he said that there is a surprise coming and we'll know the surprise by the end of September. It's not clear if he was referring to a surprise in the form of a channel or not, but that's what I think he was talking about since he was discussing the channels right before he said that. See the video below and see for yourselves.
GameHead's interview with Reggie