My project (Mithril.js) has ~2600 stars on github, a relatively lively mailing list, and it's on the front page of todomvc, so it's definitely more popular than many "competitor" projects, although not nearly as popular as Angular or Ember.
My general impression of the landscape is that affiliation w/ a famous brand helps a lot in driving adoption. Being a guy in the outskirts of Toronto, working on the project on my spare time (with two small kids), it's pretty hard to compete w/ teams that get paid full time and get opportunities to talk at big conferences in San Francisco. I'm skeptical that this kind of gap can be made narrower with hard/good technical work alone. This reality weaves deep even into the design philosophy of Mithril: one reason the project is small is that I don't have the resources to tech-support a huge complex one. Lack of time is obviously not a selling point, so the design of the framework itself needs to account for it - I put a lot of thought into reducing learning curve and framework complexity because that is something that both reduces my workload as a support person, and is itself a selling point (especially considering all the recent Angular criticisms).
I think the only reasons my project enjoys any popularity at all is the efforts I put into non-coding tasks: writing docs (took me like 2 months of writing docs nearly exclusively to get to what I consider a decent level of documentation, even despite having a tiny API), writing articles, talking to the community, getting on twitter, adding shameless plugs on HN :) etc. In a way, this is similar to being a startup founder: there's a lot of peripheral stuff to do. It's not uncommon to be spending more time on non-coding aspects of the project than actually coding.