That's the one I have as well.....25974486U Version 4.0c. for my '08 LTZ
As a point of interest, I was fiddling around with my nav unit the other day cycling between the "North Up" mode and the "Heading Up" mode and it looks like they've put in another...how do I describe it..."view"? Whereas before all you had was a bird's eye view (straight down) with either the map oriented to "North Up" or to the direction ("Heading") that your vehicle was facing, now when in "Heading Up" mode you have the option of either bird's eye or a "vanishing point" view (not the right term, I know). By that I mean instead of looking straight down on the map you now look from an elevated position from slightly behind your spot on the map and looking down the road towards the horizon in the direction you are travelling (towards the vanishing point). It's like a lot of the display orientations that other GPS units have that you see from Garmin, etc. So now there are three pushes on the North Up or Heading Up icon...North Up, Heading Up (bird's eye), Heading Up (VP).
This might have been here all along but I don't recall it and it's not mentioned in the manual. :ack:
