http://www.looprumors.com/index.php?/posts/apple_special_event_planned_imacs_with_ios/
It would certainly make sense - just look at the changes to the iOS 4; The 'Dock' now resembles a Mac Dock, which would allow for easier switching between OSX/iOS4... You can customise and change your wallpaper
The only thing that wouldn't make sense is that the iPhone/Pod/Pad has motion control for many Apps. I highly doubt people are going to lift up their iMac and start jiggling it about!!