From the specs it appears that the new 5D essentially shares the same viewfinder as the 7D and that interchangeable focusing screens will no longer be available (they also don't show up on the Canon site as they do with the 1D X).
This is likely a deal breaker for me as manual focusing through the viewfinder with the standard focusing screen, and the 7D focusing screen, is practically impossible to do accurately with fast aperture lenses. Specifically, Zeiss lenses will be much more difficult to use. Anyone who claims otherwise isn't as critical of focus as I am, because when a viewfinder can show a DOF no wider than f5.6, getting critical focus at f1.2 requires trial and error at best.
Yes, you can still use LiveView, but that is only practical when shooting from a tripod (landscapes, for example). It's too awkward to use LiveView in normal shooting conditions (for me anyway).
I'm sure I'm in the minority here, but I find this to be a bummer.