Yeah, sarcasm.

So what has this question and the answers revealed?

Have we (you) concluded that the X5 makes people sick?

Since it is 'sportier' than most SUV's it's probably driven more aggresively than usual. It doesn't explain highway motion sickness though. A friend of mine (a notoriously slow driver) just bought an E46. We pulled out of my driveway at the same time (me in my Cooper) and he FLEW down the mountain. After I realized he was no longer in sight, I tried to catch him but couldn't. Later I asked what got into him and he said "that BMW really grips the road!" Yup, they do.

I'm sticking to my theory. The turbo attached to this i6 provides such an aggressive acceleration following a slight turbo lag. I don't think people are used to it. My GF actually likes my old V8 4.4 better, probably since it didn't have the same turbo situation.

I enjoy the turbo i6 much more.

I think it is a simple case of "this vehicle is so awesome it makes me want to puke".

If you think nausea was indeed caused by the ride quality, you may consider replacing the tires to non runflat tires in order to reduce the unsprung weight, as the runflats are quite a bit heavier than non runflats.

From Wikipedia

a heavier wheel which moves less will not absorb as much vibration; the irregularities of the road surface will transfer to the cabin through the geometry of the suspension and hence ride quality and road noise are deteriorated. For longer bumps that the wheels follow, greater unsprung mass causes more energy to be absorbed by the wheels and makes the ride worse.

No difference. I have non-runflats.

Anyone else have a problem with this wiki?

I like this one...