Firstly, I do look forward to seeing what Olympus/Panasonic/Leica come up with. There looks to be room for some interesting variations on the theme.
Secondly, much to my surprise, using my GRD II, I have come to really like composing on the screen. While some of the comments have talked about difficulties in dimly lit situations, I have actually had more problems in bright sun situations (where I do use the optical viewfinder.)
But I still am looking forward to someone taking Nikon's sensor from the D300 series and applying it to a DRF, because I have become addicted to no-light (well, really low light photography). Thus far, the 4/3 sensors have lagged seriously behind in this area. I'm not specifically waiting for an M9, I am interested in seeing some kind of post-M8RD1 development.