EntilZha on 05 January 2009
I have had my Wii since launch. I lined up at 6:00am to be sure to get one.
I have had it on "yellow light" (Connect 24) for the whole time (over 2 years now!) without any problems.
It is always warm, but never hot. 
In the absence of evidence to the contrary, always assume you have the upper hand.
NNID = RangerOne
Switch = SW-2393-3671-6907
