I guess it depends on what you are trying to accomplish. The maps are outdated from the moment you get them -- sort of like a computer. I've had plenty of times where I have used a POI to find a restaurant, pull up in front of the place and its not there anymore. I've also had times where I've punched in addresses and it cannot find the street since its a newer street. If you are using it for directions to a fixed point (address) and its in an established neighborhood then why do you need an update? And what features does the new version have that makes it worth $70?

BTW - the navigation DVD for my car is $179. I don't get it every year. In fact I've only gotten one since 2005.