There is no real reason it is not available in the US. It is available on the M5 and 7 Series here.

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PhoenixM3
2008 M3 Sedan - Interlagos Blue [On Order]
2008 X3 3.0is - Black Sapphire, Sport Activity, Premium, etc.
2007 X5 4.8i - Deep Green, Sport, Premium, Technology, Comfort, etc.
2005 X3 2.5 - White, Bare bones, Auto (My business delivery vehicle)
2001 M3 Convertible - Phoenix Yellow, 6-Speed