The current platform (E70) was produced as early as FEB 2006. It officially replaced the E53 in November 2006. As far as model years are concerned, you will not find a "2006" E70. All E70s are going to have a model year of 2007 and up.

If you want to study up, I suggest going to your dealership and request a brochure. There also a number of sites that actively review numerous vehicles from different manufacturers. (www.edmunds.com, www.motortrend.com, to name a few).