Nice talk, @trek. I wish you had more time there.
I think that using jQuery UI, kendo or whatever is a hack for the time being, but we shouldn’t rely on them in the long term. It adds a level of complexibility when you try to reuse that code or make changes to adapt for your scenario.
For simple widget that shouldn’t be too noticeable. But for tables, for example, kendo and extjs probably have their on controller/view combo. And you would have to create a ember controller/view middleground to deal with that. You’ll end up with 2 controllers and probably more than just 2 views for the same widget. Imagine what a nightmare that would be to maintain and/or find bugs.
On the other hand, I guess ember developers are doing pretty fine reusing existing widgets. Otherwise we would be seeing a lot more widgets in ember than there are now.
PS: Does the DismissView exist somewhere? or was it just an example? I would really like to see a demo showing the whole thing: template/router/controller :}