I just happened to stumble upon a fresh delivered X3 while picking up floor mats from the dealer.  Although I didn't have much time (out to lunch) I couldn't resist taking it out for a spin.  It was outfitted with the premium package , auto trans & cold weather package.  Like the 5 series the pictures don't do it justice.  The interior was clean, and the dash material is more 'rubbery' than the 3 series.  It does say "Utility" more than "Luxury" but that's to be expected.  The gauges have a 3D look to them (you'll know what I mean when you see it).  
As far as the road test, I was very pleased with the overall feel over the 'ute, and pleasantly surprised by its handling and road manners.  I didn't have a ton of time with it so I really didn't get a chance to put it through its paces but I did get to cut up a few corners and some open road.  It did eat up the turns like a 3 series (not with the same confidence, though - with the higher center of gravity and extra weight and all).  The 3 liter didn't strain, but was obviously a little slower getting the 4,000lbs beast up to speed.  Breaking was outstanding (as expected).  
After my drive, I am seriously consider getting one in the spring.  The only downside was front legroom.  I'm 6'10" and with the center console design it was a little tight on the right side.  This surprised me since my 325 has enough room.  I inquired with the dealer about this to see if they could move back the stops/seat/track any more.  Still waiting on an answer.  
Hope this helps.