Ross,

I've checked for feathering and there is none present. No cupping either. I do remember my old tires showing some feathering on the front ones...but that was on the outside edge of the thread.

Thoreau,

You may be right, I am a bit obsessive-compulsive with cars. What got me worried is that the car hasn't had an alignment for about two years and I've done front upper control arms and rear dog-bones over that time span. Seeing this strange wear on brand new tires set off a few alarms. I hope you are right and its nothing to worry about (but I still found a local german auto shop that should be able to check the alignment as per BMW specs).