Something to think about. If Apple somehow doesn't have the phone you want, you will get it tomorrow or the next day with the amount of stock they are getting in. Still faster than the pre order. I cancelled mine in fear of it switching to PFS before I get there! Plus, Apple will do you a solid and give you a gift card for your troubles if anything should happen.
Good point! My main concern is being able to stick with AT&T Next - I don't want IUP.
ETA: Do we still have the same 14 days to send in our old phone?