I hope that nothing will "win" because "front-end" programming is such a nebulous concept that it's much better for each project to find a niche and cater to an increasingly narrower set of trade-offs and use-cases. The idea that we need such a thing as a "framework" is I think mistaken but understandably so: we've only had viable module systems and package management for a short amount of time and they are still evolving.

But module systems and package managers change everything about how open source ecosystems work! When you've got a package manager that is trivially easy to publish to, you remove pressure on libraries upstream to include extra functionality into their cores because users have too hard of a time fetching the functionality for themselves otherwise. With pervasive package management and a culture modularity, modules can be smaller because they can depend on other modules instead of inlining functionality or otherwise being overly cautious about dependencies. Convergence under this kind of fitness landscape tends toward narrowly-focused single-purpose libraries that do just one thing and do it well.

Popular frameworks have already severely dwindled in size from something extjs, mootools, or yui scale towards something backbone-sized. I sincerely hope that frameworks dwindle away into nothingness so that focused, reusable libraries that take simple inputs and produce simple outputs can fill the gap because the severe orthogonality and opportunities for novel recombination are so much greater!