it has nothing to do with jsx. all vdom libraries do this. redraw-the-world is done much faster than React by numerous libraries, including mine (see other comment in this thread). Inferno is a lib that will probably replace React while maintaining jsx compatibility, check it out btw.

jsx is just more natural for designers but i agree with the gp that the benefits can be obtained with plain declarative js and avoid all the tooling required for jsx.