default_run_options[:pty] = true
Capistrano no longer requests a pty on each command, which means your .profile (or .bashrc etc) will be properly loaded on each command. Some commands will go into non-interactive mode automatically. If you’re not seeing commands at CLI, You can return to old behavior by adding this line to your deploy.rb
For more changes in Capistrano 2.1
http://weblog.jamisbuck.org/2007/10/14/capistrano-2-1