0444d588_18_FeatureList___FedoraProject__Summary
[% Complete] 100% [Name] Rails 3.2 [Updated] 2012-08-13 [Summary] 
Rails 3.2 is the latest version of Ruby on Rails stack. Fedora 17 still contains Rails 3.0, which are rather old from the Rails community point of view.
Releases/18/FeatureList - FedoraProject