I bought on release day, but I'm now on my second handset.
Current handset was manufactured on 11/20/2011.
I've had the following problems on both phones:
-Mic mute problem on some (not all) calls
-GPS intermittently shows wrong location
-Navigation intermittently selects an insane path taking tons of backroads through neighborhoods - this is not to avoid traffic
-Compass intermittently fails - doesn't detect the direction I'm facing or the fact that I'm turning
-Camera intermittently fails with a "Camera is not responding...." error. When this happens, alternate camera apps like Vignette don't work, either