JD, I just checked and it seems that Apple changed the charging voltage for its ipod and iphones introduced on and after September 2008 from 12V to 5V. If you had an earlier cable (or another brand), then the 12V will definitely fry a later model Ipod/Iphone. The newer BKR2 is definitely designed to provide 5V. charging and so is compatible. If you are not planning on upgrading the sound, why not just purchase the new cable:
http://www.discountcarstereo.com/iP-BKR2.html