Falafelkid has posted a rumor on his blog:
"Mario & Sonic at the Olympic Games will get some strong competition, at least on the DS. An announcement regarding a big sports title will be made at the Leipzig Games Convention in three weeks. A Wii version may also be in the works."
Normally I could care less about sports titles, but he said it'll be competition for Mario & Sonic at the Olympic games, so it's not a sports title like Madden or anything, so that's why I'm intrigued. I guess we'll have to wait and see what it is.