UPDATE: If you're having issues accessing Northrend in Europe, log out for around 5 minutes (out of your account) and then log back in. Your account should update properly to be flagged for Wrath of the Lich King.
We're getting reports from many EU players who are members of the World of Raids community that Wrath of the Lich King is now live on European servers. Players are able to create Death Knights, and of course travel to Northrend, if they have an upgraded account. We'll work on getting screenshots up as soon as possible. Stay tuned for more updates
Thanks to Odin of EU-Turalyon for the screenshots. Click on them to see more proof from his screenshots, such as exp gain, etc.