oh great. Since when you make the final say about the behavior of taskbar? First, I don't believe you one bit. Show me exact MS official document on how taskbar MUST behave. Second, after that, I can still say your old bible is old and you are not the pope of me.
He may not be, but I am the pope of you.
Seriously, I see his point. A lot of Metro apps you just want to go in for a second and then leave; like visiting a website. I'm not used to closing them, yet, so I'm surprised some are still sitting on the taskbar, and then I close them. In a web browser, you expect to just navigate away, not have to close every site, same thing.
On the other hand, I think it makes sense to show them on the taskbar, as we're moving to both windowed Metro apps and using a full-screen vs. windowed metaphor. So I figure its just something I'll have to get used to.
Unless there's some better solution.