You know... there is only one minor issue I have with it. If you have the phone directly connected AND blue-toothed in, the phone needs to pick which audio out it's going to use. There is no ranked preference, just who connected last.
Given how wonky MFT is about starting up, it's really a crap shoot. I would like iOS x+1 to let you rank those options like you can with wifi nets on OSX.
USB gives you graphics on MFT and is a little more responsive. Bluetooth doesn't give you graphics, but allows you to continue using the iPhone screen controls (useful for rewind 30 seconds). So, there are merits to both.
I spend most of my time on an hour one-way commute listening to books. So, I'm looking to charge my phone and being able to occasionally rewind. The ideal way would be to get power from usb and use bluetooth. I initially tried to get a 6" male to female usb cable and cut the data connectors - didn't work. It wouldn't charge. But it looks like someone has commercially solved this: http://eshop.macsales.com/item/Newer%20Technology/CBLUSBCS1M/
I haven't gotten this yet, but it looks ideal. I think I'll just wait until my next macsales purchase of a hard drive for my laptop to roll it in for the shipping cost. I hate paying as much in shipping as things cost.
But, ya know. It really isn't a big deal to kick it over to Music and select the appropriate connector - sync or dock connector.