[s-cars] Speaking of Ipods NAC

[djdawson2 at aol.com]

I am admittedly uninformed about the Ipod world.  So realizing that I know nothing about them, I'm wondering if anyone could bring me up to speed.
 
I'd love to use it as a complete music source replacement in my cars.  Despite owning a couple of fairly high dollar Nakamichi head units, skipping is still a frequent annoyance with stiffer suspensions and tires.  I know that there are some interface options available for getting Ipod signal to a car stereo... but the ones I've seen seem inappropriate for high fidelity.
 
So... my questions:
1) Is there a high quality interface available for car stereos?
2) I don't see hi-fi type specs related to Ipods.  What is the sound quality?
3) Is the signal coming from an Ipod equivalent to the signal quality from a nice CD player?
4) Wide frequency response?
5) 90+ db signal to noise ratio?
6) Does anyone make a head unit that effectively serves as an Ipod controller?
 
Anyway... any enlightenment would help.  Sure seems like it would be nice to replace skipping and large quantities of CDs with a box the size of a small calculator.
Thanks,
Dave