In my experience the jsx stuff works rather nice and looks like html where javascript just happens to be the templating language (apart from some gotchas listed here: http://facebook.github.io/react/docs/jsx-gotchas.html). And IMHO it pushes you to build small components which fit nicely together in the end.

But then, I like the full javascript approach from the mithril framework too and I haven't build something complex to date.