As everyone probably knows, NW and DL are offering 10k bonus miles if you fly some of thier new international routes. I recently flew a domestic itinerary and received:

Summer Europe Mega Bonus Miles 5,000
Summer Europe Mega Bonus Miles 5,000

I received a total of 10k "accidental" miles. What are the chances of NW taking the miles back? Has anyone received these miles too? I wonder if I will get the bonus miles of every domestic itinerary? 10K bonus miles + 100% Gold Elite bonus is pretty dang amazing on cheap domestic runs.

Am I risking the miles by sharing in this post?