Install vcprompt: https://bitbucket.org/mitsuhiko/vcprompt

If you want fancy colors in the Terminal, you will need the SIMBL
plugin (http://www.culater.net/software/SIMBL/SIMBL.php) as well
as the TerminalColors plugin.  I have a fork of it on github that
is configured to compile for 32bit and 64bit and works for Snow
Leopard (http://github.com/mitsuhiko/terminalcolours).