Per a discussion on the Ravelry Baby Blanket forum I made the blanket w/o the openings for the straps. Thick blankets, particularly this one, prevent the straps from keeping the baby secure in the seat and some hospital personnel have visions of a baby falling out in the event of an accident.
Blanket is made with double strands of Bernat worsted and #11 circular needle. Dark color makes is particularly hard to photograph. Click on photos for better view.