I know we're not yet done with the current season of CBS' The Amazing Race, but when Kevin and Michael were eliminated, but interested in the show definitely dropped a notch (go Nat & Kat!). However, there's already been some solid speculation on the next season, based on sightings, and it looks like it's going to be an all-star edition with contestants from previous seasons.
So... who's on season 18? There was actually some really early buzzy talk that Kevin and Michael would be back, after a supposed sighting at LAX, but those rumors were quickly dispelled. Somebody was apparently mistaken, and that's not happening. However, it does look like Ron and Christina from season 12 will be back. As I recall, they were fan favorites who almost made it to the finish.
None of this information is confirmed, and this is all early buzz. So we'll have to wait and see. For some very spoiler-y speculation, go here.