http://www.wireless.att.com/coverageviewer/

If you check the box about mid-way down it'll show you the difference.

After checking out what i just saw... i'm actually probably not going to adopt the new iphone (as 3G networks aren't available in my area)... i may just wait for a quad-band android-based knock-off... which i pray will be released sometime before the end of this year... it gives me something to hope for...