I've been researching front-end frameworks based on Google's Material Design guidelines. I post here the most popular and developed I've found. At the moment they all seem to be in varying stages of advancement, with none a clear out-and-out leader (as Twitter's Bootstrap has become for example), and it is interesting to note how each framework owner interprets the defined guidelines that Material design recommends. Here is a short summary.
Google own Material Design Light (for websites)
Hot off the press is Google's own web kit: at time of writing, a little short on components - but well implemented and documented and comes with a CDN so getting started is a cinch. Even though it's missing some items I would like, I am starting with this one hoping they will be added soon enough.
This is my current favourite - a nicely implemented (attention to design details) and good set of available components. No quick CDN for css and js assets, but there is an npm module.
A nice Material front-end kit, not so replete with all the components we would like, but pretty nice. There are some good integrations of this kit with platforms such as Meteor. Also well-implemented on the design details.
One of the more diffused option it seems, although I'm not so keen on the design implementation. However, it has some great JS components that I haven't seen with the other kits, and some good integrations with npm and platforms.
Ionic Material Framework
If you're an Ionic user there is also a kit in, possibly early, development. Design finesse slightly lacking, but very welcome components available and of course very handy integration with Ionic.
Surprising lack of design adherence and implentation touches in this kit from Zurb, producers of Foundation.
If anyone finds any more frameworks, post a comment below.