There hasn't been an expansion this glorified since Rome began conquering territory outside Italy.
Azula, that is one of the most awesome responses I have ever read on the subject. I will try and give my own thoughts though.
If New Vegas is a gloried expansion, so was FO2, and that turned out pretty darn well, some of my personal problems with FO2 aside.
More game companies should recycle their engine and assets to focus more on gameplay and story, and the world would be a better place. A world where game reviewers had to rate games on real meaningful principles, just like movie reviewers (try to) do. A world where PC players wouldn't have to constantly upgrade their hardware to continue to enjoy a franchise.
I agree with the tough to please bastard that is Jim Sterling - "If it is an expansion, it is an expansion worth $60."