There could be some east west divide. But is seems to be widely used, for instance Germany seems to prefer dots. Someone has compiled a table here https://gist.github.com/mlconnor/1887156 not sure about it's accuracy.
Imho, everyone should use ISO8601[1] as standard. Then there'd be none of this 'it's an american who wrote it so it's the month first for some reason' rubbish.
I'm an American that prefers YYYYMMDD and has used it exclusively in my career. As a developer with a lengthy deployment background and it's simply the superior way to go for dates for readability and sorting. Many like myself have 2 modes of operation, the 2nd being what business owners and executives are expecting. We couldn't force it on them if we wanted to. This often extends into English vs metric as well. I default on metric for everything I can. It may not be the American developer to blame but the average person around him. It's very surprising to me that after the American Revolution, we weren't eager and early adopters of the Metric system considering animosity towards the British was still lingering for some time.