I have an xperia arc (f/w 4.0.A.2.368) and a 2008 Ford Edge with Sync and navigation. Here's my experience:
Sync is able to pair with the phone via bluetooth, making and picking up calls work just fine.
Phone book synchronization also works fine, except for names with non-Latin characters, they show up blank and I can't dial them from phonebook. Call history also syncs fine.
In media playback mode, the sound is properly routed to the car speakers, the only problem is that it breaks up a lot when the phone is trying to connect to a wifi network (this happens when I am in the garage, where the phone already sees my home wifi but the signal is too weak to connect). I can use the play/pause button, but NOT the prev/next buttons, which makes the feature practically unusable.
Also, I have to manually launch the music player on the phone to play music, it doesn't just launch by itself when I press "play".
Text messaging doesn't work at all.
I wish you guys could fix all that in the next f/w release...
