So, this is for the people who just got the game and can't connect online. Please read these possible solutions to get you connected online, before making a thread:
1. Is this your first time playing an online game on your wii, or going on the Wii's wifi in the first time? Have you turned on Nintendo's Wifi Connection yet in the first place? If its the latter, you need to go to the main menu, and click settings to establish connection to Nintendo's Wifi. Go here for online connection support:
http://www.nintendo.com/consumer/systems/wii/en_na/online.jsp2. Create a second profile and log-in wifi with that profile. You should be able to log in now. Then, sign out, and log back in with your 1st profile. You should be able to log in with your first profile. This seems to be the most common fix to log-in for a good amount of people, and is the most recommended before trying other ways.
3. It could be due to server downtime to fix bugs and glitches.. Its only been a day, so Treyarch will get things fixed up soon. If it takes too long to log in, check to see if there are any other threads first to see if others have problems (sometimes the wifi or servers have a down time and closed by Treyarch or Nintendo to fix bugs) try again a few hours later. You should recieve a five digit error code. If you do, read #5.
4. Using a LAN adapter? This could be the problem. Many people seem to be having trouble logging in as well as online matches being occasionally frozen, while using lan adapters for this game, for some strange reason. A possible solution? Switch to using wifi and see if you can log in. For many people, simply switching to wifi seems to fix the problem.
5. Can't seem to connect to wifi in general (this means all your online multiplayer compatible wii and/or DS games as well as your wii channels like Opera and News that use Nintendo Wifi)? If this is the case, Nintendo will usually give you a 5 digit error code. Note that there are many error codes, and that each error code represents a case by case situation on why you can't connect to wifi or to an online game. Potential problems could be issues dealing with connecting to your wireless router, or just Nintendo/Treyarch closing the servers temporarely to fix bugs/glitches.
To figure out what that error code means go to:
http://www.nintendo.com/consumer/systems/wii/en_na/errors/index.jspand type in the error code in the box.
In addition, you can also google your error code along with the keywords, "nintendo error code" and it should bring many results. Usually people on forums will explain better what the problem is, then the automated and technical responses that Nintendo have, on their website.