Replacing Prototype/Scriptalicious with jQuery in Rails 3?
I'm not sure why there isn't more information on the interwebs about this but if you want to use jQuery as your default javascript library in Rails 3 it's as simple as replacing your rails.js file with the one here:
https://github.com/rails/jquery-ujs
After that just delete controls.js, dragdrop.js, effects.js, and prototype.js and add jQuery in their place. I prefer adding jQuery via the Google CDN but go ahead and do whatever makes you happy.
Happy coding.