I'm very familiar with the iTunes syncing sort of deal, so when I went to get a new phone, and I wanted a new iPod, I thought that I'm very familiar with iPods, so why not get a phone that operates almost exactly like them?
I had a touch too, so I was familiar with how they worked.
Traded my touch in for the phone and REALLY glad I did. The second gen touch is way better. But I won't be getting one. I'm looking at the new Nano now...
I can't see choosing the touch unless you either don't carry a cell phone (yeah right) or can't get service from AT&T (or your equivalent provider abroad). I mean, you could do a regular cell phone + ipod touch and save some on the monthly bill, but IMO the convenience of only carrying one thing is worth that cost.