If  you make an offer to someone for a Box of Books, how long do you wait for a reply? A week? Do you keep it out there indefinitely? Do you delete your book after a few days? Does it depend on the book?

I give it a week. If they are books I am really interested in reading, I'll send a polite PM asking if they are interested in the box of books offer I sent them. After a week, I just remove the offer.

I am not a boxer, but I would think it would depend on how badly you want to make the offer.  I personally, wouldn't leave it indefinately, I think my max limit would be about a week.  After that I would just figure they are not interested.  I think they should reply though, seems rude to just ignore an offer, whether you accept or deny.  At least then the other person can try and offer to another person, rather than just waiting for a reply that will never come.  If someone took longer than a week to reply I would just try and offer someone else.