There are a few ways you can drain the water out or prevent it. If you can find the hole where the air pocket busted, make sure you drain most of the water out of the hole by squeezing on the air pocket where the hole is, then fill the hole with silicone, and after the silicone drys, no more water comes in. Sometimes if i cant find the hole that was busted, you can at least drain out the water every other set or so (depending how quickly the water is filling up)
I have a couple friends that have just drilled a hole in the heel of the air pockets, so they can just drain out the water after a set.
Next season they are doing away with the air pocket system, I have heard. Personally I really like the air pockets, they feel so nice while im riding but once I bust them, it can sometimes be a hassle to keep your boots from getting heavy. I ride the 2010 Watsons and the pair I'm riding right now havent been busted yet, and I have been riding them for probably around 2 months. I have had pairs that have bust within 2 weeks of riding them.