How would Rails be bumped to Ruby 2? Does Rails 4.0 depend on it? Or will it be a 4.x thing? Just trying to get my head around this, since some of these cha

How would Rails be bumped to Ruby 2? Does Rails 4.0 depend on it? Or will it be a 4.x thing? Just trying to get my head around this, since some of these changes seem quite integral?