I'm guessing it depends on how good your internet is and the amount of people trying to access the website. Since it is the day the dream world is meant to be available in quite a few countries, there is going to be a lot of traffic and so it will probably take ages to access it. Also, I'm assuming the level and type of Pokemon you tuck in doesn't play too much of a role, although according to the manual some Pokemon can't use the Dream World. I'm using a CHANNEL Jirachi and I can access the Dream World. :S