Well, I thought this topic was dead. But, it seems to be going and now an idea.... if we did what you are saying, donaldejose, and used a High Definition Electronic Viewfinder with a 30mm X 30mm format, we could have a V1 with the definition of the D4/D800 dependent only on the sensor characteristics. But, is there not a problem with the live view and continuous auto focus that would need to be resolved?
I actually believe at some time in the future, the mirror camera in which the mirror moves will be a thing of the past. Some technology which would allow a mirror to have a mirrored surface due to an electronic signal, then become clear when the signal changes, this would allow a standard TTLR viewfinder but would work at 60 FPS. Then the 30mm square format would be a no brainer, maybe combined with 36mm X 24mm. Did someone say D5?
Sony already has a headstart with the a77 24mpx at 12fps (sure the buffer sucks) but one look at it shows that when expeed 4 comes out the possibility of a TLR D5 is huge. In additin the fact that electronic shutters are creeping into dslrs proves that vdslr's and tlr's may merge at one point or another...