Take a look at this awesome touch screen display similar to the Microsoft Surface that we have seen so much about. This system differs quite a bit in its operation as well like using Linux for one.
We don't need gesture support in X. Gestures depend a lot on the context. A gesture in one context can mean something different in a different context. And the only thing that knows the context is the application. This is very similar to a button press. Pressing a mouse button can mean a zillion different things, depending where and when it happens. That's why all X does is relay the button press to a client application, which then does the right thing.