If you’re in a country that observes daylight savings time and you use WordPress, don’t forget that you must manually change the time of your installation to account for time change.
On Sunday at 2 a.m., the clocks moved forward one hour. My installation, needed to be changed from GMT -5 to GMT -4.
It’s a bit annoying it must be manually set. Surely there is a way to either use the time of the server or ping a time server somewhere for an update.
http://ottodestruct.com/blog/wordpress-plugins/automatic-timezone/
And then there’s this – http://core.trac.wordpress.org/ticket/3962 – which I opened two years ago.