I received my ATT refurb last friday. It looked and worked fine except that the battery never fully charged. It would get to 95% or so and the lightning symbol stayed on always. It never showed the little plug symbol in the battery. This morning, Tuesday, at 9:30 am it started to get hot in my pocket. In fact, it got burning hot and the screen was flashing all white then all black. I held down the 2 buttons and the screen went black and that was all she wrote. I went directly to the local Apple store, it opened at 10 am, I walked in without an appt., handed my HOT phone to the first person I saw. I walked out with a new phone at 10:15, activated and ready to use. A quick restore at home and it's like new again. The phone I received from Apple was completely up to date (1.1.4) and shows warranty until 4/09 on the Apple website.
Good luck everybody!