It's working on my DC, there were a number of visitors on my server this morning at 5 am Eastern US. All of the hardware running the game is at max load right now so things may not work immediately or may have issues from being overloaded. SE posted a statement about this on the Lodestone a few days ago. They've done everything they could possibly do to improve the back end of things. All we can do is be patient and expect there to be things like this happening due to the unprecedented number of people playing the game. Helpful, but non-essential, functions like World Visit not working is a whole lot better than servers crashing all the time.

Please be patient and understanding of the situation and try to enjoy your time in the game.