Since I'm no programming nor javascript wizard, I needed some help from Jeremy. I know my way around MVC since I've been doing some Ruby on Rails in my time.

My experience with more advanced Javascript is with MooTools, so I found it familiar to build Class-like objects. I rather enjoyed the experience and I'll be using it to replace the codebase for my more complex project.

The documentation is exhaustive and with that example app, annotated et al., it's even better. I also am very confident in Jeremy's skills as the project maintainer, he helped me a lot and has proven he creates great Javascript libraries.

The API seems stable enough. From Backbone 0.1.2 to 0.2, there weren't that many differences in the API, mostly nice additions.

I've already used it for my admin app as well, and in the process submitted some patches to backbone as well. It's quite nice how unobtrusive it is. I wrote a small jquery plugin that converts a form & table into fully functional crud with client & server side validation.