I'd say get the E for Architecture, I currently use a Medium Format Digital Back for my Architecture shoots, It has no AA Filter and I rarely have a problem with Moire.
I think the real limiting factor here may be the Glass, the samples on the nikon site of the E are a bit underwhelming to my eye when compared to the files from my 22pm back shot through Rollei (schnieder) glass.
Believe me I would much rather use a Nikon DSLR for that stuff IF it was as good as the MFDB file or even very close...when viewed at 100% the samples are much softer and lack the detail of the MFDB files at 22MP.
Now I normally would not even compare the two but Nikon brought it up ! I will most likely rent a D800E when they come out and do a proper test...Here's hoping !