I seem to recall that at some point during this series they have positively identified Jerry's neighborhood as the Upper West Side. Can anyone confirm this?
In regard to points a and b, check out the Sunday Times sometime, or even the Voice, and you'll see that there is actually a great deal of housing available on the East Side for lower rent than comparable accomodations on the West Side. This surprisd me, too, when I was comparing prices. The East Side is much bigger than the West Side, and thus has a greater variety of lower-priced housing, and it's not as cool an area, in my personal opinion. I've lived on the West Side (2 blocks from Tom's) and I currently live on E. 72nd, and I much prefer the company on the West Side to that of the East Side. Of course, it also has Park Avenue et al., which are as expensive as it gets anywhere!
The transportation is not as good either, as there is only one subway line (4-5-6), and when it's late or out of service, everyone is screwed. However, it does stop at Astor Place and at Bleeker Street, which are just as close to NYU as the 1-2-3.
Robert