In NY, AT&T's "Mark the Spot" iPhone app is going to run constantly. It lets you pinpoint precisely where AT&T's network sucked, and how—dropped call, bad data, crappy voice—and send it to them. Prepare for a tsunami. [iTunes]
I'm actually very impressed with this app. What they DO with the data remains to be seen, but the impression I get from the app is that they are serious about collecting good data. It's well designed with several reporting options, and the ability to pick a location on the map is top notch. I just submitted two reports for areas I know are poor (but overall I'm happy with AT&T coverage in the Sacramento Metro area, and it has recently gotten a LOT better in the SF Bay Area, where I frequent).
On a side note, this is also a handy tool for quickly picking the coordinates or street address from a location on Google Maps.
In a way, this almost seems like a tool for network techs, not the average dumb consumer. It's nice that AT&T is giving its customers the credit to use the tool properly.