I am in the market for a new phone also. I have AT&T and have had them for several years. I like the rollover minutes! I have 4 phones and 450 mins. a month, plus nights and weekends. I have never used all of my mins. I talk with people in my network a lot so it doesn't use mins. I went to the AT&T store yesterday to see about the phones available. I am seriously thinking about the IPhone! It has and does everything! It cost's $30 a month extra, but that includes the GPS, internet, email, music, pictures, videos, games, text messaging, etc. I like the hands on features and love the fact that I can make things larger. It really helps at our age!
The phone is not cheap, $199 with a contract, but I think it will pay for itself with just the GPS function. Now I don't need to buy one of those! Just my thoughts...