Ember is still going strong, Octane is a fantastic new release and it’s been awesome to un-learn all the ember specific things in favour of all the new vanilla JS ways of doing things that Octane makes possible.

About the only negatives I can bring up are IDE (and other sorts of vendor tools/components) support/integration is not as good as more popular frameworks like React, but that’s really just to be expected as vendors tend to target based on popularity.