Used to have AT&T and the coverage is pretty bad in my area. Forced to switch because of it. With Verizon I have a signal practically everywhere. But like Strubes said, not an iPhone guy either. I'll stick with Android.
What a tool. They may call it "Minecraft World Explorer" but all it is is a seemingly annoying to control Minecraft Alpha that lets you load uploaded worlds from the web. I'm not a hardcore fan, but this isn't going to have a good impact on the game itself. And why would they need this anyway? Mincecraft can be played on Mac's. It even works on Linux If people wanted it, they could pretty much use an iPad if they configure it right (or Notch does it himself).
This app just looks like a money grabbing scheme to me.