I went in to sort my TBR pile by wishlist as I noticed that it was now an option and it only listed one at the top as being wishlisted but still kept others throughout the list.  Am I doing something wrong?

Theresa

Mine did the same thing.

I don't think so (that you're doing something wrong, that is).  I noticed this option after the update, and I'm not entirely certain that it works as intended just yet.  I get the same result as you, with the rest of the list showing alphabetically after one WL book.  You might want to send in some feedback by way of the Send Us Feedback button in the Contact Us page to let them know.  That's how they observe and fix most glitches, I think.