I just spoke to the dealers Business Manager.

Evidently there was a short lived 45,000 mile restriction, but that has been waived. You can buy the Powertrain Plus, Gold or Platinum up to 50,000 miles or 48 months from start date.

Pricing for 2009 X35d with 48000 miles

5yr/100K/Gold = $3410
6yr/100K/Gold = $4070
5yr/100K/Plat = $3810
6yr/100K/Plat = $4570

Service = 6yr/100K = $2495.

She said these are the MSRP from BMW. Also said that for the diesel there is a 60K service and she thought one additional service that is covered by the warranty in addition to all the oil, brakes, etc . . . I have to check the Warranty Booklet.