Not many bright ones in here it seems. As Coldfire has said the world servers aren't yet up. Patches are normally always released during a games downtime so that when the game is back up people can just log right in and play. If they waited for all server to be up and then permit people to download the patch nobody would be logging in for a long time due to everybody and their mother hammering the system.

In short this is nothing new, most online games do this.