When should I purchase my X5?

[dbot16]

Hello,

I'm a first time poster, long time reader.

I am looking for some advice: I am going to purchase my X5, but I am not sure when I should.

Initially, I thought the new iDrive interface was coming out this spring, so I waited until now. But then, I read that the iDrive interface, plus facelift and new engines were coming in the fall production, so I decided to wait until then. But now, I am reading that some (it not all) of these featues will be out in spring of 2010?

Can someone give a definitive timeline on when these features are coming? I really don't want to have to wait another year to buy my X5. But I also know that I won't be happy if I buy one now, and the above features come out within a year.

Thanks in advance!