RoR and client-side MVC

Hi. RoR does a great job with MVC pattern in the server-side, plus it´s
integrated with great javascript libraries: scriptaculous and prototype,
but these libraries are not mvc frwrks. (not that this is a problem)

It´s yet a relatively new topic, but I think client-side mvc frwrks are
catching up. To name a few:

1. JavascriptMVC: http://javascriptmvc.com/
2. SproutCore: http://www.sproutcore.com/
3. TrimPath Junction:
http://code.google.com/p/trimpath/wiki/TrimJunction
4. Axiom Stack: http://www.axiomstack.com/
5. Archetype : http://archetypejs.org/

And now comes the doubts:

1. Is it really a good idea to use mvc pattern in the client-side?
2. If so, mixing directory structure from some client-side frwrk with
RoR will be very confusing
3. Maybe the best thing is wait until RoR integrate some of this frwrks?

I´d like to hear some personal opinions in this suject.