I just turned Gold this year and did my first long-haul flight last week.
I flew to Tokyo from Sweden, in very cheap Economy (class M). I checked in online, but when I dropped off my luggage they issued a new boarding pass without saying anything. I didn't think much about it until I looked - whoops, upgraded to business on Copenhagen-Tokyo! I had a great flight with a two-seater for myself.
Very pleased with my trip so far, I was quite relaxed about the return, since I already was placed in Economy Extra. But there were more good news - at the check-in counter in Tokyo Narita, I was informed that Extra was full, and I had automatically been upgraded to business! Another great flight, another two-seater by my own, right at the front this time.
Walking around the cabin in each direction, the CPH-NRT flight was indeed full in Economy, but Extra was about two-thirds capacity at the most. Returning, Economy and Economy extra were packed to capacity and Business had only a handfull of seats left.
I have been Flying Bue Gold/Platinum for many years, but upgrades have happened very rarely, and never on an outgoing flight. Now I am for many reasons thinking of moving all my business to Star Alliance, and if the upgrade pattern will be anything like this in the future, that's one more reason...