spent 4 weeks in june/july going from miami to los angeles...not having a car is going to be rough in most places...i forgot my drivers licence one time going to phoenix and rode the buses for 4 days...managed to do half the stuff i planned...any possibility of signing on for zipcar in some of the cities?

other cities/towns? places i visited which i could see being nice to live/work and friendly to a walking/biking lifestyle:
- key west: resort town feel, new urbanism before it was called that
- miami south beach: happening place, very design conscious
- fort worth: whereas dallas downtown feels unfriendly, fort worth is very unexpectedly lively, makes this list but barely; kimbell and the new modern are must sees
- austin: although better with a car, the place seems very livable and up to date, great entertainment town
- phoenix: really cheap real estate if that matters, some of scottsdale is nice and walkable, but otherwise a car is better
- LA: assuming you're based there? i love the place and would live there if i could get a decent job
- also consider chicago: didn't go there this trip but it ranks way up there with boston (lived in BOS for a few years) for great architecture, cultural amenities, people, transit, walkable areas, food, etc..
- and how about some canadian content - vancouver's downtown is immensely walkable and a much talked about model for downtown city planning in north america

- places that probably wouldn't make your cut that i did visit include: new orleans, atlanta, dallas (but go see piano's nasher gallery), san antonio, orlando, biloxi...

Well, considering I can return home pretty quickly, I'm planning on going 48 hours to each city without sleep and perhaps setting up my flights so I can sleep on a plane or sleep in an airport.

I already have found really good deals on hotels in NYC.

I'm not necessarily going to tour great architecture though. I'm going to scout places out.

It seems this might be a good exercise in planning because I'm already realizing how hard it is to be a "pure pedestrian."

I second Chicago. Insanely easy to get around, too. Buy two one-day unlimited transit passes at the airport and you're good to go.

absolutely new orleans. transit options are ok there, now that the street cars are back up and running. you'll need to take a few cabs, but luckily most of the things you want to tour (neighborhoods) are pretty concentrated.

I always tell people to visit pittsburgh... not sure if jet blue flies there... but the bus system there is randomly pretty excellent, which helps you. There's even an airport express bus that will get you into town for $2 or $3.

Steven Ward keeps telling everyone to visit Louisville, KY and it has always sounded interesting. There's also St. Louis, Milwaukee, Minneapolis / St. Paul,

I have been wanting to visit Savanah, Charleston, Nashville and Asheville (SC), but you'd need to check how car-friendly they are.

In a sense, you might have better luck touring the smaller cities on a tight time budget; I've done two 3-day trips to NYC and both left me frustrated and feeling like I hadn't gotten to see anything, missed more than I saw, wasted my time etc. (It's annoying when you get back and everyone's like, "did you see such-and-such?? did you see this other thing??" and you're like, "NO, I spent most of the first day just getting my shit from the airport to the hostel and secured, and then I didn't have time to go all the way uptown and check out X, so I mostly just walked around the neighborhood!" or whatever.) Smaller cities are great in 2 days, you get the sense that you really saw the place and you don't feel the crush of overwhelming time restraints. Plus in smaller cities it doesn't suck up 45 minutes of your time just to get across town on the train, for example.

Historic Savannah is surprisingly pedestrian friendly in the historic part. If I was going to pick a perfect american planning model, Savannah would be pretty close.