I crossed 1MM in the middle of August, and my tags showed up in the mail today.

The purser on my 1MM flight stopped by my seat to congratulate me during boarding, and asked if I'd be ok with them making an announcement about my milestone. The captain also came out to greet me and allowed me to go into the cockpit for a picture. Unfortunately we ended up having an eight hour delay because of a volcano eruption, so that original crew timed out. The replacement crew didn't mention me crossing 1MM, but that was fine with me as I just wanted to get the trip underway.