bee2, if you belong to a big corporate body, maybe there are discounts already in place between BMW and your company. Ask your HR department. Quill said because this is a new 320d, there is no pre-reg option for now-usually in December, they start doing the pre-reg 6% discounts to get rid of the current year cars.
If you don't want the iDrive but still want a brand new 320d, there are still many performance-kitted 320d units available and you could probably get a massive discount-I think at least 6% off the list price. The performance editions have the side air vents and their rears and fronts look meaner.