Just joined the club, got mine (A6 2.0 TDI Auto 2008) about 2 weeks ago, do a lot of motorway miles, this car is a dream to drive, compared to BM's and Mercs that I've had previously its a joy. Love the interior layout too, everything is .... just.... well....sensible lol.
In ref to 2011 sat nav question, my 2008 model has 3D maps, one slight annoyance is that the nav doesn't give you a countdown to next turning/action, it does show on small screen, but not on centre screen.
Just had fab integrated bluetooth telephone system installed, now works like original OEM, and clear as a whistle. I went for the VIseeo system, and it all works perfectly.
The boot space is a thing of beauty, could easily fit the Albanian Mafia Boss from Tope Gear (anyone see that episode) in there lol.
All in all will almost certainly stick with A6 from now on.
Cheers Neil.