I don't have one but I seen them and they are actually very bad in my opinion. I don't find them to be very useful and they don't have any cool features that other things don't have. I rather just stick with my Android phone and the great phones with it.
The name is stupidly funny, but the concept is pretty cool. It's basically a hybrid of a console and a handheld. It's still not so appealing to me though, I want them to release a better Wii or DS (or both?). Kinda feel like Nintendo hasn't been very successful lately, but the only thing they have going for them is their franchises.
I assume gaming companies are trying to get the family-based console, the Wii, into their system to find some new gamers. A lot of adults use the Wii and have never played shooter games, so I wouldn't doubt that is what they are aiming for.
It seems like it will be pretty fun because it is going to have a lot of great games, I think, but I believe it will be over expensive and won't be anything majorly new.