Most of the rest of the world has a large Diesel market which lessens the economics of hybrids. The US is now starting to get diesels but in a limited number of models. As an example, the US can't get the 40d variants because of homologation issues, but they can get the 35d which we no longer can.

The X6 was US only at launch and only later did everyone else get it, so the same may happen with the Hybrid X6. I guess it's down to market forces.

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Me:
Current: 2011 E71 40D Vermilion Red/Beige Nappa

Wifey:
Current: 2012 R80 Countryman SDX Green/Cream