I think Google’s My Maps is a big milestone in Google Maps. Announced today, it scores big over other map websites, and most likely they are going to follow suit soon. My Maps allows you to draw over existing Google maps, and create you own stuff – roads, houses, whatever. You can then save the changes and make it public or unlisted. If made public, your map will be available to people as “user-created content”. If kept unlisted, you can still share the URL with your friends.
I moved into a new housing community last year and the streets are not yet shown on any map website. Even a year after people started living here, even satellite maps show the place as a large construction site. Which makes me wonder how often do these websites update their data. So, if I am inviting people over and want them to look up driving directions on the internet, I know it is not going to be possible. So, I have to give them directions myself. 
Now Google’s My Maps gives me a way out. All I need to do is draw a few lines for roads, and fix a balloon (placemark) for the location of my house, save it, keep it unlisted and send a link to my guests. When they click on the balloon, they get an option to get driving directions, which of course gives directions to the nearest listed address. Good enough for me.
To each placemark, you can add a title (road name, building name, whatever), and a description. The description is a text box that lets you add html. You can use the html to embed images and even videos.
