We were on the May 8th Magic. I first went to Guest Services with my pillow case and the CM (male) said that they no longer would provide this service. He said that we had to get the autographs on our own.
I then brought the pillow case (which was going to be a surprise to my daughter for her birthday, but I had to show it to her to get the autographs) with us to an autograph session, and the CM (woman) said that the characters could not sign the pillow case, but she would be happy to take it and we could pick it up in a couple of days.
So that is what we did, but I found it interesting that the Guest Services CM would not even try to get this done for us, and the character helper CM acted like she was really happy to help us.
As a side note I have to say, we were on the Wonder last year and I was really surprised at the overall service level of the Magic vs. the Wonder. On the Wonder all CM's seemed to bend over backwards to do anything to make our trip better. On the Magic I was met with no's on simple requests and nastiness on others.