Not sure whether this is a brick or hardware failure...

OK, I just tried to safely update to 4.1. Don't lecture me on that, I have my reasons.

Anyway, the Wii is now basically inoperable. It will turn on with the Wii remote. However, the Wiimote does not stay connected, and cannot input to the Wii. It also will turn on with the power button on the Wii itself. It will only turn off by pulling the power cable, or by holding the Wii power button.

No output is being sent - black screen, no audio.

So what's the deal here, and what needs to be done to fix it?

This could be caused by a low level faliure of boot0 boot1 boot2 or NAND. Your wii can be fixed using savemii, but it will require some modifications.

I am not to sure how to fix this type of brick without savemii, though i am trying on one of my wii's that are bricked like yours.