[glhaynes]

It seems to me that one of the main benefits of desktop apps is that they are tightly coupled to the platform. Great cross-platform apps are very much the exception.

So my vote goes to web for cross-platform while heavily optimizing everything else (everything client-side, at least) for the one platform it natively runs on. I don't see great user experience coming through a different route.

If you do need native capabilities client-side, hybrid apps that embed a UI built using web technologies are a potential option sometimes, too.