I am looking at buying a charging dock for 2 remotes. Is it better that the charging dock take its power from the USB or the Power Cable? Apparently if it takes it from the USB the Wii must be on for the remotes to charge?
Power cable. It will charge faster this way. The USB slots are the standard 5v I believe. Also, the Wii would simply be put into standby mode to charge while you are not playing. Standby mode is when teh led power light is orange instead of red.
You're right about the max power output of the USB ports but they do send out power while in standby mode. I've got a hub attached to the Wii and the hub lights are on while in standby indicating that the hub is getting power.