I've used both Backbone and AngularJS, and found the AngularJS learning curve to be steeper than the Backbone one, and there's more 'jargon' to grok before you

I've used both Backbone and AngularJS, and found the AngularJS learning curve to be steeper than the Backbone one, and there's more 'jargon' to grok before you start understanding things. How steep you find a learning curve is likely to be influenced by your technical history. That said, the difference in difficulty, in my experience, is certainly not an order of magnitude.