"Go to Address" is the cool one. It saves a couple of steps (copying the URL, pasting the URL, and pressing Enter/Return) to go to another page/site. My testing has been limited, but to help Safari figure it out, highlight a plain text URL that contains the "http://" protocol prefix.
Highlight the following URL/plain-text (in Safari) and see for yourself: http://www.apple.com
[robg adds: Now that's handy!]

