The location on my profile page it has changed from NRW to North Rhine-Westphalia.
However, I did not edit that value or field myself. Did someone else change it?
Why did it change?
We're doing a best-guess match on locations across the network in an effort to get more consistent location formats for all the users, for example mine would be "Winston-Salem, NC", "City, ST", or "Something, Ontario" for Canada, "London, United Kingdom".
To do this we needed to perform a backfill of locations across the network, but we can't do this instantaneously since we're hitting against Yahoo's API to do this (which would more than likely ban us for a massive hit like that).
It's unfortunate but we will get a few false positives in here...we've reduced that as much as possible and checked many of the matches to ensure the correct location's being returned...but some will slip through, and we apologize for that. In the future this is done from your profile, rather than on the server-side, so whatever location you leave in that field after this we'll respect (but still recommend the match we found on the right optionally).
The process doing this is rolling through Stack Overflow right now (meta was done earlier) and will finish on the rest of the network tomorrow.