I checked the baby food section of my local CUB supermarket today.

[MineralMan]

There were gaps in the stock, primarily on spaces labeled for Similac products made by Abbott. Other brands of infant formula products were on the shelves, and didn't appear to be in short supply. There were no shortages of products targeted for "toddlers."

Of course, I have no idea what the stocking situation is at any other stores, nor whether people are skeptical about feeding a different brand of formula to their infants than what they normally do.