Beaujolais Nouveau and B. Villages Nouveau

[quijote]

This question occurred to me as I was looking at another thread: Are the Beaujolais Nouveau and Beaujolais Villages Nouveau drinkable within just months of their bottling? This is what I've been led to believe, but....

How is plain old Beaujolais different from B.N. and B.V.N? It was stated on another (the Novice) thread that regular Beaujolais from 2001 is a good bet now; why wouldn't that vintage be past its prime at this point?

None of my books really gives a good answer for this. I recently tried a 1999 Beaujolais, and it was darker and more tannic than the BVN I've been drinking. Is its longer drinkability related to the tannins in the liquid?