My co-workers 625 did the same thing. He claims his recording capacity has been increased to 150 hrs of SD from 100 hrs of SD. There must of been new software that was pushed through, but removed all scheduled events.
Same thing happened to me today. I got home from work a while ago to find that Hell's Kitchen, Deadliest Catch, and The Universe were not recorded. When I checked the guide, all of my HD channels were missing, as in not even in the guide, no red, just not there at all, except for HBO, MAX, and 1 HD PPV. I did a reboot, and they all showed up again, but all my timers from any HD channel were no good anymore. I had to delete them and start over. I am wondering if this is a glitch in the L449 software in the 622. I hope this isn't going to be a regular occurence.
Same thing happened to my wife's 625 a few nights ago. I posted about it in the technical forum, only to come to the conclusion that it was hard drive corruption. Perhaps not, if you guys are reporting the same thing.