"Blankets are OK but they can slip and slide, plus your hands are trapped inside." Darned if the Snuggie people haven't found their own pet rock!
I have a better idea for when you're cold: put on a sweater! Or if you really want to look like a jerk but don't want to spend the money: put your robe on backwards.
But I have to give them props for awesome marketing. People all over America are probably buying the "blanket with sleeves" -- and I'm just mad at myself for not thinking of the idea first.