I work for Target. There was a system wide message on WorkBench, internal messaging system, saying that EVERY Target store will get one case of 5 iPad 2's to be held for sale on Sunday the 17th, as they are in sales ad circular.
This is not an abnormal policy, back during the holidays, XBOX Kinnects were held when they were in an upcoming ad circular.
So while an online tracking system may indicate inventory, they are not supposed to be sold until Sunday.
This is no different then what Best Buy has done or is currently doing.