I'm a newbie to the forum, and just took delivery of a mystic blue '06 X3 with all the bells and whistles yesterday as a replacement vehicle for my recently totaled '04 silver grey X3. I must admit that BMW has addressed and corrected a several minor annoyances present on the '04 model.
The most noticeable was that the '04 version was noisy as hell. Lots of annoying squeaks, noisy moonroof, etc. Not so, in the new (and presumably improved) '06 model. Yay!!

But then again, it's only been one day!
The aero kit II is standard, which ROCKS!
And I just LOVE the body coloured bumpers, although I fear that'll change as rocks and bugs do their thing.....
I'm interested to find out what other people think...