Games Workshop have posted the rules for the 2011 Armies on Parade competition.
From their website:
Armies on Parade is your chance to plan, collect, model and paint an amazing new army, display it on a two foot by two foot board and show it off in all its glory in your local Hobby Center. All our Hobby Centers around the world will be holding a Parade Day where everyone in the store will have the chance to vote for their favorite Army on Parade.
Every store winner will then go on to proudly represent their community at Games Day, where all the winning armies from across North America will be on display and the ultimate Armies on Parade champion will be chosen. If you are attending Games Day, not only will you have a chance to see all the magnificent armies, but you will also get to vote for your favorite making the North American winner the true hobbyist’s champion.