I saw that too when I ordered mine a few weeks ago.
I thought it would be nice if there was a group email address that the discount could be sent to so that everyone here got a chance at a discount. Something like
[email protected]
Of course it would be easy to abuse something like that.
BTW: The Bentley E46 manual is awesome. It is like the mother of all owner's manuals. It should be standard issue with each new E46. Get yours now!