To be supportive of History API and not much weight.
Only, preferably, not the first link from Google, but what really had to do with it. What's the pros, minus,grabs.
http://documentcloud.github.com/backbone/ In my view, the best js MVC frimevork.
- http://arturadib.com/hello-backbonejs/ - Five great lessons.
Most importantly, after reading, make the right conclusions:
If you only need a spleen with buttons plus minus-- away from MVC, pee on your forehead, you can use "Jquery/Dojo/MooTools/MoiLoveAyax_ Library.
If you need 20 of these buttons, write the jquery/Dojo/MooTools/MoyaLove_
If you need to write an interface to the Gmail/Google docs/Facebook, look towards MVC, Observer, etc.