I'd love it if it were Reeve. It'd make sense since, with the exception of Palmer, all the other Shin-Ra executives were killed, which would make him "Mr. President." It'd also explain why we haven't seen Cait Sith in any of the trailers. On the other hand, there's no evident reason for Reeve to be in a wheelchair, since he was fine at the end of FFVII, and he probably wouldn't want to have anything to do with Shin-Ra, Inc. anymore anyway.