VERY good question, reader Ashley. There certainly are similarities between the two — i.e. they both create expansive, airy, puff-like pastry objects — but in the end they are quite different devices. Popover batter resembles something you’d use for crêpes. Choux batter is a more complex mixture of pre-cooked (gelatinized) starch that’s lubricated by fat (egg yolks). It seems to me as less a food than an edible, ultra-elastic paste, one that will heat will increase in volume by up to 600%. Popover batter can’t quite perform that feat. Indeed you’re lucky if popover batter increases threefold as you bake it. It’s still darn impressive though.
That said, you can use popovers and choux in similar ways. Certainly the classic use of a popover is as a “bread” eaten with a main meal. However being hollow, popovers are great filling holders too — you can put custards and mousses inside of them, even soups or stews if they’re aged and a bit stale. Makes for a very nice lunch on a chilly day!
Thanks for a great question, Ashley!