"We all know books burn -- yet we have the greater knowledge that books cannot be killed by fire. People die, but books never die. No man and no force can abolish memory... In this war, we know books are weapons."
I've never seen any pattern in where I get catches at all. Of course I've probably gotten more over the years at places where I've left quantities of books, rather than just one or two, but other than that, it's always a surprise when one gets caught. I have no release spots that I'm confident will result in catches at all.
I find that places where people are surprised to find a book lead to a higher catch rate. OBCZs and book exchange shelves come with very low catch rates; hanging a book from a tree next to a hiking trail will typically result in better chances of a journal entry. Of course, it all depends on how you define success! If by 'success' you mean making someone happy, then some of my best releases have been when I gave books to homeless people. Catch rate: zero.