The X3, X5 and X6 BMW’s produced ion the BMW facility near Greer, South Carolina drove U.S. sales up in December and for the year.  The company reported Tuesday that sales of the X3 increased 63.6 percent. X5 sales increased 12.1 percent in December to 3,939 units and December sales of the X6 jumped up a whopping 53 percent to 859 units, compared to 562 units during the same month of the previous year. The X3, X5 and X6 segment accounted for more than 18 percent of BMW’s total U.S. sales in 2010. BMW of North America LLC said it Read the Rest…