You're correct on Windows. There is an option to set the time zone automatically, but I don't know what percentage of users will have that activated. For mac/iOS/Linux/Android I expect the changeover will just work by default. I noticed that mac/iOS pushed out timezone updates last week. zdump -v /etc/localtime is showing a chance to CST on Nov. 1st.
I administer some systems, including older systems where I have to update tzdata manually. Noticing the switchover to CST on Nov. 1st is what brought me here, as it just seemed like an obvious error to me. Reading through all of the threads on the issue, I at least understand the reasoning. As an administrator, if I started seeing CST in log files or the output of the date command, I would be - and indeed was - confused, and forced to go track down the reason - and I knew full well about the coming time change. Seeing -06 in logs would not be confusing at all, I'd say it's already 50/50 whether a logfile uses 'MDT' or '-0600' for the timezone offset. Of course, for the vast majority of users, this is a non-issue, as they will never see the tzdata abbreviation anyway. -Patrick
