While I have noticed others complaining about an easily nudged mode dial, I personally never had an issue with it.
There are a few people whom have had calibration issues with the focus mechanism, but that was easily addressed by a trip to Nikon service. And while there were people with legitimate calibration issues, a good number of the early soft focus issues were due to user error.
Another known issue early on that affect only a small amount of units was the lubricant spray caused by a defective seal on the mirror charging motor. I was an early adopter of the D7000 in which it was affected by that issue, and it was repaired under warranty by Nikon and I have yet to see a reappearance of the lubricant spray since the repair.