I'm also in the market for a new 2011 X5 i35d. Actually may be putting in my order this weekend for sure.

Total savings from MSRP i've calculated for my build is ~$7609 without further haggling. I think you've got a lot of room left to negotiate. At least $1000 plus

Perhaps you can do what i did. Order the consumer report X5 detailed report. From that report you can use their "Build and buy" program that dealers participate with. The lowest quote I received was 2.4% markup over invoice on the car and all options/accessories were charged at invoice price.

Give it a try. The report is $14 and you can get it instantly through email. Guaranteed you'll save hundreds to probably over a thousand from your current offer