So is PA just grabbing random PA titles to tweet, or are authors actually paying to have their books mentioned in PA's tweets?
I suspect it's inevitable for PA to eventually sell a promotion service to its authors and one of the ways they'll promote their authors will be to place announcements on Twitter. Of course, PA will use a contract that mirrors their book contract so they don't have to do anything more than necessary which would likely be a bare minimum. I can see it already when the Tweets state that Author Y's book resonates and asks others to retweet. I wonder how long it will take PA to come up with enough different promo announcements to let us play PA Bingo?