Setting all lists and bookshelf to private-- is this an alternative way to put your shelf on hold without missing out on any offers?   I  found a member with an interesting profile and wanted to PM her, but she has an unpaid membership so I can't PM her. Then I noticed she has all her lists and bookshelf set to private too so I can't even try to order anything from her.

Private bookshelves means no one can see the bookshelf and order directly from that member.  Their books are only accessible thru the queue. 

Ah, a staunch FIFOist !

I decided to try setting my bookshelf to private.  I not a FIFO purist but I'm testing the privacy thing.  The way I see the book order system is I don't have to find a member who has a book I want .  I order the book and the order goes to next in the queue.  However if I happen to look at someone's shelf and decide to order from them I see nothing wrong with that.  I think the team set up FIFO for easy ordering.