From what I know, you're allowed to bring anything on the plane, minus the obvious and also no liquids. So if your carry-on has any kind of liquids (i.e. mouth wash, etc.), you will have to check it. Apparently, someone brought liquid explosives onto a plane recently. Someone always has to ruin the fun for everyone. But, as far as I know, the only change is liquids. I would also assume you wouldn't be able to bring any types of drinks as well.