I agree with Nathaniel 's point, but I think that it just means that for Meteor there is a larger market and revolution to take on. Meteor's mission is to replace .NET and Java on the app development area, not just supply them with a cover. I think the best overview about that is here in Geoff's talk - youtube.com/watch
I hate the "popularity" questions but I think there is no doubt that Meteor is getting super popular since version 1.0 and the trend is amazing, even more then Angular when I first started using it: google.com/trends/explore
Another important point is that when seeing and talking to other companies I mostly see that their biggest problem is usually not Angular vs. React but the overall stack architecture, and that's the biggest strength of a Meteor app.