WP7 is a good system I do enjoy it.
Why?

I spent two (probably a lot more) hours teaching how to use "touchscreen" "next generation" device to a friend who can barely use WindowsXP.
Over time, she'll be proficient. I couldn't have done that with iOS or Android because the learning curve would've been too steep I think.

And remember this is one person. There is probably a thousand of these who eagerly want to get into these "futuristic gadgets" to each one of us. As long as they're buying, Microsoft will happily be selling.