I was browsing through one of the other forums and a frustrated 720 user had emailed tomtom about not being able to upgrade his maps. The following is the response from tomtom that he posted.
I guess we will see...
Thank you for contacting TomTom Customer Support with regards to your 720
There will be a v7.10 free update for 720 users, We hope to have this avilable later next week
Our apologies for the inconvenience
With Best Regards
The TomTom Customer Support Team
I guess we will see...