I have had a book on my WL for a while now and my number came up a couple of weeks ago...of course I immediately requested the book.  that was on 11/20.  The sender accepted it a couple of days later and marked it to be shipped by 11/30.  Ugh!  10 days???  So, I was a little annoyed, but accepted it was a holiday week--even though I requested it more than a week before Thanksgiving.  I am also a little perplexed that you can mark that you will send it by Sunday at midnight when Sunday isn't a usual mailing day.  The book still isn't posted as sent and people on the WL behind me are getting the book!  I would cancel the order, but I don't want to go to the end of the line for the book!  So, I'm still waiting...

Okay, rant over...

The options for "I will mail by" are just the next 5 days--it doesn't adjust for non-business days.

 I am also a little perplexed that you can mark that you will send it by Sunday at midnight when Sunday isn't a usual mailing day.

If the person is using any form of printable postage they can print out the label and drop it in any blue box on Sunday. I do it all the time.

I can use the APC machine at my post office and mail books 24 hours a day.

they also have 2 days past that date to mark it mailed. 

Members have 5 days to accept a book request and then can choose to mail it up to 5 days later. That's how the 10 day figure came into play.

Maybe they mailed it on Saturday, but wasn't able to get back online and mark it mailed until Sunday.

I should also mention that it has not been printed out yet, so it has not been mailed.

Well, cheer up!  In the worst case in a couple more days the request will completely time out and you will be placed back in first place on the wishlist and (as members behind you on the list are getting copies) another copy should be along shortly.

Some people don't have PC access every day.

Some people don't have cars available every day to get to the post office (I personally can only mail on Wednesdays).

Some people only get paid once or twice a month and have  to wait until after payday to mail things (I only get paid on the 15th of every month).

It doesn't really do any good to get impatient - you don't know someone else's circumstances - all it will do is raise your blood pressure if you worry about it too much.

I'm may be a little impatient about getting the book, but I am more disappointed.  If you say you are going to send a book by a certain time, then do it.  It is flat out rude to extend it out the maximum amount of time and then let it just expire...especially a WL book.  I have been waiting for this book for a while already. 

I understand people have different situations, but if you can't send a book within the alloted time, don't accept the request. 

The label has yet to be printed, so I expect the request will time out tomorrow and I will be back waiting on the list.