Here is a video cast describing the upcoming features of the Ruby on Rails version 4 by Andy Lindeman

The following are the highlighted features;

  • Rails.queue
  • strong_parameters
  • Turbolinks
  • Russian Doll Caching (cache_digests)
  • ActionController::Live (streaming)
  • PATCH verb
  • Routing concerns
  • Extraction of activeresource
  • ActiveRecord::Relation changes and improvements
  • Removal of plugin support (not gems; only those that are installed in vendor/plugins)
  • Removal of Rails 2 finder syntax
  • Deprecation of most dynamic finders
  • Deprecation of eager-evaluated

I believe yet again its going to be a killer Web Development Framework.