I've got Robins and Mockingbirds who have taken to feeders too. The pair of Mockingbirds watch for me to enter the yard and fly right to the spot on a tree where I spread peanut butter, waiting no more than a foot from me. It's amazing! This has been going on for a couple of years now. One of the Mockers flew into my 2nd floor bedroom once via an open window but that's another story.
I just had a pair of Red-wing Blackbirds show up this morning, and I have quite a variety of woodpeckers, some of them huge! Some of the woodpeckers and Chickadees all but ignore me when I approach the feeders. Most of the others stay pretty close by. The Cardinals remain timid. There are a lot of them. I've never had so many Cardinals in one yard, that I remember, at least not since I was a kid. My great-grandma had a perfect garden and an incredible number and variety of birds.