Altador Cup
The Altador Cup was announced by Neopets on 31st May 2006 to commence one the 2nd June. It is a sporting event with teams from sixteen Neopian worlds participating. The Altador Cup appears to be made to co-incide with the FIFA* World Cup in Germany of 2006, and if the golden orb seen in the preview trailer is indeed the 'cup' itself, it bares remarkable resemblence to the actual World Cup.
The game played to win the Cup is called Yooyuball. The gameplay appears to be based on Jai alai. The ball is actually a rolled up petpet called a Yooyu, and comes in several different varieties: fire, snow, Mutant and Faerie. The rules of Yooyuball are explained on the Altador Cup Rules page, though the role of the Neopets player and Neopets' system of ranking the teams is still unclear. Until June 8th, Neopets users can select the team they wish to join/support and change teams if they wish.
It is uncertain how Neopets players will participate in this event: it is believed that either players will be supporting (and maybe betting) on their team, or that they will be be playing as part of their team in a localised competition rather than a community-wide competition.
Altador Cup - Team Rosters
According to the Altador Cup page, sixteen Neopian worlds will be participating, each sending a team to compete in the Colleseum in Altador. There is also a seventeenth team, the practice team, who appear to be from Jelly World.
The shields of these teams can be seen on the path leading to the Colleseum in the preview trailer, and are now available for viewing on the Altador Cup Teams page.