I like being able to see how much play time I've had on there as well. The fact that they post all that information when you've been playing on any of the channels is quite interesting.
So, do you use the Wii Calendar? How about posting letters to friends over wifi? I've posted a few. I've had fun with the picture taking option of your game stats in Mario Galaxy, and posted that to a friend who has the game as well. Getting letters from friends is nice as well. I wonder if there is a way to make the Wii blue light flash when you want to be reminded of a certain "post" you put on the calendar? I'll have to look into this further.
Anyway, that's my bit on the Wii Calendar feature. Keep Playin!