Reasons why I prefer backbone: - It's lightweight. I am a bit obsessed with client-side optimization, so that's a plus in my eyes. - I am not a big fan of bin

Reasons why I prefer backbone: - It's lightweight. I am a bit obsessed with client-side optimization, so that's a plus in my eyes. - I am not a big fan of binding via html attributes. Yes, there is a way to do that script-only way in Knockout too, but it was neither fun nor appeared very clean. - Backbone allows to use either jQuery or Zepto as DOM manipulation library. - Backbone is template engine agnostic. The situation with templating in KO seemed a bit muddy to me. - Backbone has routing built-in. With KO I'd have to use something like Crossroads.js thus adding even more weight. In short you may need to write a bit more code in backbone to get the same that you can have with almost no code in KO, but on the other hand Backbone feels much more flexible and less restricting. YMMV.