Seems like low-level brick but Wii-motes work

Ok, so I'm only bothering to actually post this so others in my situation can find it and double-check things.

I just updated to 4.2U, almost accidentally. After the update, everything was working, so I didn't think much of it. On the next bootup, I had absolutely no video or audio. Aw crap. Something with HBC and 4.2 went bad.

I spent an hour and a half trying to find my exact issue on this forum, among other places. Then, as I started typing this post (specifically at the part about whether Wii-motes work) I remembered something from the very beginning of the troubleshooting process. Pointing the Wii-mote (which paired and sustained a single light) at the screen prompted force-feedback. Uh...

Turns out... my auto-switching AV hub had been bumped. I had checked the AV cables, but not the mode the hub was in. This post is a reminder to triple-check those connections, especially if you get Wii-mote force feedback.

Thanks to everyone else out there who gives information and helps with troubleshooting - truly appreciated!