The current BMW X3 is based on the previous 3-Series generation (E46). As promised, the new BMW X3 that will be produced from 2010 on will be based on the latest 3-Series platform (E9x), in particular from the touring (station-wagon) version E91, as you can see below 
(from X3 World :: Next Generation X3 Test Mule?)
Update: I’ve just noticed now the objects on the roof, tied up to the roof-bars with some elastics. 
Those are probably there to simulate the hundreds of kilograms that the X3 weight more than a 3-Series touring, and to make the gravity point a couple inches higher. This would be a great 4×4 3-Series E91 anyway.
More concepts:
(via AutoZeitung, X3 World and BMW X3 2010)
(…) 2010.
Уже идёт тестирование шасси X3 под кузовом Е91
http://blog.litux.org/2007/06/27/bmw-x3-2010-spy-photos
Concept (…)
(…) gelassener
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Sieht ja gar nicht mal so eckig aus der Nachfolger - wenn denn die Fotos stimmen. Die Quelle ist aber bekannt für gute Erlkönigbilder.
http://blog.litux.org/2007/06/27/bmw-x3-2010-spy-photos
Sieht schon nach der Desginlinie wie beim X6 aus. Na wie gefällt der Neue?
Der spionierende Gelassene
(…) The current BMW X3 is based on the previous 3-Series generation (E46). As promised, the new BMW X3 that will be produced from 2010 on will be based on the latest 3-Series platform (E9x), in particular from the touring (station-wagon) …
BMW X3 2010 Spy Photos - Read More… (…)
I have a x3 which is great looking and great handling. The 2010 style is digusting, looks like a stationwagon. I will buy a 2009 and hope you change the style.
(…) http://blog.litux.org/2007/06/27/bmw-x3-2010-spy-photos
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I’m looking to buy gray M3 front seats or regular gray sport seats. Let me know. It’s for a coupe. (…)
We have the current BMW X3 and we love it, the new one if it comes with the twin turbo engine it will be awesome.
@fastcars: who cares about the X3-35? Why would one want to have so much horse-power when in most countries there are speed limits, and when the fuel is so expensive. I mean, we have the more conservative Diesel engine and it’s already near to €100 to fill up the tank!
(…) Salinas (Asturies) Vehículo: BMW X3 150cv
Posts: 787
BMW X3 2010 Spy Photos at Litux Blog
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