I'm looking to buy a used C63 AMG. What are the differences from 2009 and 2010 version.

A search will yield a thread that has all the information you desire.

I don't recollect what the thread is titled.

Biggest difference is the IPOD interface. On the 09 it only shows on the command screen behind the steering wheel and you can only navigate it with the steering wheel buttons. On the 2010 the complete IPOD menu shows up on the NAV screen and you can you use the command control knob to navigate it. Way much nicer.

Yeah that's major, but there are many more differences, again, all outlined in that thread.