I gave it a quick try on my T-Mobile Dash by adding an event. The agenda view (list of events) is the only view available on a mobile device. I went to the regular PC to flesh out the information (I could type faster there). Adding the address for an event lets you use the mobile version of Google Maps from a link on the event.
Microsoft Pocket Streets used to integrate with Contacts on Windows Mobile devices. But, now that it is gone, I guess that this Google feature could be handy (unless you are out of tower range :-). You can find Google Calendar at: