Hey there.
Everyone's probably busy with Christmas preparations so they tend to focus on the game when they have time during this period. =]
As for your problem, it might help if you try to connect again a few times. My friend had a similar problem: he couldn't see the server list for the whole day. Then late in the evening, the game let him in. He just tried repeatedly (waited a bit, then tried to connect, and so on). Of course if you're tired of trying like him, just go away doing something, then come back and try again.
Or you can.... try reinstalling the client.