My brand new Q7 (20" rim) keeps on drifting to the right. I took it already 2 times back to the dealer. They say this happens on all Q7 20" (I don't buy that). They say the alignment is correct and I need to wait up to 5,000 miles till the suspension kicks in. If I wait that long the tyres will wear. Has this happened to anyone?

you notice it more in some cars than others. Most roads are angled to let water flow off and that's where you feel it. I've found that more basic roads don't cause the car to drift whereas highways do.

Bear with me on this one. I tried already in many different roads including roads angled to the left (some roads with ample scape lanes on the left) and still drifts to the right.

align it on Monday. It has less than 500 miles on it. I will keep you posted.

I am taking mynes to the dealer again today for the 3rd time. I talked to Audi and demanded an explanation.
You should ask for your alignment report. I believe my dealer knows already what the problem is though they are not willing to admit it. It might be a wheel problem, meaning they have to change it.
Will keep you posted

My Q7 with 20's started drifting more noticably after the 5K service. Maybe they rotated the tires? Not too happy about it, but I know I'd be must less happier trying to deal with them to make it drive straight. Not fun.

This is a great picture and depicts clearly the situation. It's really a cross to carry!!!
I got another round of my fight today. Back to the dealership I requested the alignment report on the previous services and guess what? They haven't done the alignment altogether! Brought the issue to the dealership manager. So I've got a loaner and yet the car another another couple of days at the dealership:
1st get an alignment actually done and check whether within specs
2nd get wheels rebalanced
3rd start moving tyres and rim and see what happens

Some of the Audi dealerships I've been going to (for the last 9 years) don't even do in house alignments. Such a pain.