OP you said it yourself. You can get more money selling the 4S and paying for the 5.
Also to everyone that is in the f-it boat-
I was in that boat. I didn't want to pay the extra $250 for a 5. I spoke with AT&T very diligently, and figured out I can just start a new line for $9.99 per month. Why would anyone want to pay an extra $120 per year for an upgrade? Because:
1. If you do the math, it's cheaper than $250 per year. Yes you heard me correctly, you would have to pay that $250 next year for an eary upgrade too.
2. AT&T gave me free text messaging for 6 months. I have a family plan and messaging is $30 per month. Therefore, $180 over all.
3. AT&T gave me $10 per month credit.. For the rest of my life, if I chose to stick with them. Yes. That's right.
4. I rarely make calls anymore due to the fact that I work a lot. The other line on my account rarely does too. Most of my usage is text messages- sometimes 15k a month but lately 1-3k. So I agreed to down my plan to 450 min per month and I still get to keep my rollover minutes of nearly 2500. Saves me another $10 per month.
5. When my phone arrived, the new number I received was already associated to another account, making it difficult to activate my phone at home. For my troubles they credited my account for $35, out of nowhere.
The 5 is an amazing phone. I used it for 6-7 hours last night playing with it, using the camera, etc. picked up my 4S and it felt weird. The 5 is significantly lighter, and you will notice. It's a phone that just pops out at you. I have a cover on it, but dang, by each minute that passes, I just want to take it out of the cover and look at it. I wasn't so amazed by the new design when all the leaks happened, but now, I think it's an amazing looking phone. I'm very happy I made the upgrade.
All in all, OP, make some calls, talk to some CS agents. Be nice. Some will tell you, sorry there is nothing they can do, but they are lying.