As soon as I got home this afternoon and saw this thread, I checked my 622 and it was fine. Then tonight at 8:00 I noticed that it wasn't recording something it was supposed to, so I checked and all my timers events for today had been deleted even though I had guide data up to 10:00. I had no guide data after 10:00 as far as I could tell -- I say "as far as I could tell" because it wouldn't let me scroll forward! I rebooted it, and the guide data came back to normal but all my events for the rest of tonight were still deleted. Timer events for the future seem fine except for the fact that about once a day there's a re-run scheduled to record on a timer that's only supposed to be recording new episodes. Normally when this happens it seems to only apply to events where the original air date isn't listed, but all these do have original air dates! What the heck is going on? I could understand if there was a problem with the guide data being broadcast, but why is it hitting everyone's receivers at different times? I can't make any sense of that.
By the way, could someone change the thread title to something meaningful since it seems this wasn't an isolated event?