Does anyone know the differences if any between the 07 and 08 DVD Nav systems in the Tundras?

Nav system is the same, the map/software disc was updated sometime late 2007.
Early 2007s got the ver. 6.1 disc
Late 2007s and 2008s got the ver. 7.1 disc
(7.1 has a few updated maps, little tiny bit different software and interfaces, and the voice recognition seems to be a bit better/more intuitive).

I wouldn't pay for the upgrade from 6.1 to 7.1, but if a friend with a 2008 Prius happens to let me "demo" it, I might sample it as a trial for a week or so...

So they still lock you out of some functions of the Nav while driving then?

So they still lock you out of some functions of the Nav while driving then?

Yes, but both can be re-burnt into a hybrid DVD that uses the 5.1 loading file and you can override the lockout.
http://www.tundrasolutions.com/forums/tundra/109282-diy-navigation-unlocked-sucessfully/

Or you can purchase or build a speed pulse generator to override as well.
http://www.tundrasolutions.com/forums/tundra/110944-diy-all-nav-functions-all-time/

Also please don't post the same question in multiple forums. Your posts will be moved and or deleted without notice.