For anyone who's looking for the changelog, it's at the bottom of the page so it's easy to miss.<p>* Made the return values of Collection's set, add, remove, and reset more useful. Instead of returning this, they now return the changed (added, removed or updated) model or list of models.<p>* Backbone Views no longer automatically attach options passed to the constructor as this.options, but you can do it yourself if you prefer.<p>* All "invalid" events now pass consistent arguments. First the model in question, then the error object, then options.<p>* You are no longer permitted to change the id of your model during parse. Use idAttribute instead.<p>* On the other hand, parse is now an excellent place to extract and vivify incoming nested JSON into associated submodels.<p>* Many tweaks, optimizations and bugfixes relating to Backbone 1.0, including URL overrides, mutation of options, bulk ordering, trailing slashes, edge-case listener leaks, nested model parsing...