In a couple dozen cities for now. VZW is working on having their entire 3G network replaced by LTE by mid to end 2013. AT&T will be late to this party of network upgrade and I don't know what they'll offer or if they'll have a larger geographic US coverage.

I'll probably switch because I use VZW for my wireless internet and between biz, landline internet and home phone I already give AT&T enough. Also, voice+data isn't a dealbreaker for me.

However, I'll also see how they shake out price wise- if there's competition for my business, I could stay with AT&T if the price was right.