Motortrend has a pretty good track record, so I'll believe them. Also like I said in the other thread, there are no major US autoshows after NY, expect for LA, which is even more unlikely IMO.
If we are including the test mule (modified 2 series prototype) I think its closer to 3 years and 2 months.
http://f30.bimmerpost.com/forums/showthread.php?t=1069185