I don't know if you have these over here yet but they have their own amplifier so they will play music through all of your car speakers whether or not you have a telephone input
You can fit them with or without a cradle as the screen shows you all the caller id and playlists (including album covers)
There's also a new cradle out with a pass through connector that works if you have a skin fitted to your phone
click the link for more info
http://www.mobileinstall.co.uk/iphone.html
Oh and hello by the way, My name is Rick and I'm mad about iPhone car integration as its how I make my living

You can fit them with or without a cradle as the screen shows you all the caller id and playlists (including album covers)
There's also a new cradle out with a pass through connector that works if you have a skin fitted to your phone

click the link for more info
http://www.mobileinstall.co.uk/iphone.html
Oh and hello by the way, My name is Rick and I'm mad about iPhone car integration as its how I make my living