The connect nav + system is made by Marelli (electronic division of group Fiat). The system has five main screens... 1)Main - a overview of what the system is doing or whats is working (GSM, GPS, Cd-Changer or radio) 2) Audio - a more detailed screen of just the music options (like a complete list of all the cds in the cd-changer) 3) Telefone - more option for the phone... you have to be in this screen to manualy dial numbers and get more options on the phone system 4) GPS - options of the gps and shows several modes of the map 5) Trip - all the info of the on-board trip computer but all on one screen.
You can have the phone working, with gps working and listen to music al at the same time... when a call is made the music is automaticaly muted.
The system is great, but as zeroseven said it does not play MP3... only later on this year will a version of connect come out that will play MP3 and that version will not have the 5" TFT color screen.
There are some strange situation when the connect+ system does not seem to work 100% with the cd-changer.. but not all the time.
If you can afford it get it.