All these excuses, defending this issue remind me of Apple fan boys defending any flaws with Apple products. I know, because I am an Apple fan boy and I do it all the time. Vibration and road feel are two separate things. My 2006 330i had excellent road feel and never vibrated. I could feel the texture of the road, but on a smooth road, the steering wheel was always still and stable as a rock. If the vibration was in anyway related to road feel, it would be apparent at ALL speeds, not just the range that people are complaining about.
I tolerate flaws in Apple products, because for the most part they are very good and the pros outweigh the cons (for me anyway). I think as several posters have eluded to, this is sort of the same thing. They like the rest of the car so much, that they are willing to put up with it. Personally, any sort of vibration in the steering wheel, visible or tactile, totally ruins the driving experience and would not be acceptable in any car, let alone the Ultimate Driving Machine.
For those of you with problems, don't let BMW off the hook so easy. A BMW should not vibrate. Ever. At any speed. I can't imagine BMW would intentionally engineer a steering wheel to vibrate back and forth at certain speeds. This definitely sounds like a flaw. Reminds me of Apple's antenna-gate. Hopefully they issue a fix soon. If I plopped down $50 on a vibrating car, I'd be PISSED.