I often receive emails containing addresses in them &mdash where to meet for dinner, the location of my friend's new apartment, etc. To find out where these places actually are, I have to copy the address, open up Google Maps, and paste it in. Today, we're making it easier to see maps of all the addresses you receive in Gmail and Google Buzz.
Enable "Google Maps previews in mail" from the Gmail Labs tab under Settings, and any time you receive an address or a Google Maps link in an email, a preview will appear containing an interactive Google Map of that location. Any Google Maps URL will work, but we currently only extract US addresses (we're working on making addresses around the world work).
Additionally, when you paste a Google Maps link into the post box in Google Buzz, it'll automatically fetch an image preview of that location that you can associate with your post.
Source : http://gmailblog.blogspot.com/2010/06/google-maps-previews-in-gmail-and.html