It's all a bit disappointing really though. There is an interview with Shigeru Miyamoto and some WiiWare developer videos but apart from that it's pretty much commercials for Ninty's big releases. Which you could have gotten on GameTrailers.com.
You can rate the games you've played for more than an hour allowing Nintendo to gather an understanding of your tastes which is quite cool.
I see the potential but I was expecting more - I thought there would be release dates and previews, etc. Maybe it's not into full swing yet but I'm a little underwhelmed to be honest.
There's also the possibility of downloading DS Demos which is a nice feature but none of the games features on the demo list are particularly new so, again, disappointing.
You will want to download though: a) because it's free and, b) because Miyamoto-san is on there.