I ask as I'm looking for a new JS library for a project to build the client-side interaction, and I have no idea what is different than backbone from the rest, just that a lot of folks here are interested in using it.
* With backbone's models and collections, i can organize my application structure better. It's not easy but result is a clean code.
* Backbone's Router is no-brainer.
* Syc allow me to use RESTful JSON requests. Even i'm not using it, it's good to have such an option.
* Data-binding is a plain pain. You have to write your own code but there is always a library that you can use (eg. https://github.com/derickbailey/backbone.modelbinding ).
* I can always read the source code and thanks the comments i can understand most of it. My complain about good and advanced tutorials not because of the laziness, it was because saving time.