I ordered the D800. The D800E was tempting until I realized I was upgrading from 24MP (my D3x) and 12MP (my D3s, which is being replaced by a D4), and, given my needs, it's a bit ridiculous to want a smidge more detail. I could just hear my colleagues saying, "What!? 36MP isn't enough???"
Given that most of my photos are published in 5x7-inch size and smaller, rarely blown up to huge enlargements, and when I need to crop in on a detail of an overall product shot 24MP has proved to be more than enough, I'll probably feel a twinge of "because it's there" but will find that the D800 will do a great job.
Should my circumstances change, I can't imagine I'd have much of a problem selling a D800 and buying a D800E in its stead six months down the road.