I've basically confirmed that something about my wired connection is causing the Apple TV to behave badly. Random disconnections from iTunes, unreliable AirPlay, hanging when trying to browse to my computer, etc. All fixed if I switch to 5GHz N over wireless to an Airport Extreme. I have multiple other computers on the same switch as the ATV which get tons of traffic and work perfectly well, so there must be a defect or unfavorable interaction with the ATV and the switch. Obviously you would expect a wired connection to be more stable and reliable, but that just isn't the case. The other things I've done is to never let the Apple TV go to sleep. Those two changes have left me with a relatively stable frontend to iTunes on my TV. Curious if anyone else can confirm my experience here.