Well over here (Sweden) its pretty much "official". My BMW dealer told me there will be a facellift, the car magazines mention the new facelift and most of the german BMW forums talk about the facelift as well.
In reality of course this doesnt mean much since it seems to be impossible to actually find out what the facelift is all about.

Along the same lines though I thought it was "official" that the new X5 was going to be bigger and have a third row of seats, some people here reject that pretty hard so now I am just confused at least when the X5 is concerned.

But I am pretty sure there will be a facelift for the X3 in 2007...