07-07-2013 07:33 PM
It appears that that is not a lendable book. If you check the book page for a lendable book (Catching Fire, for example) you will find the "Lend Me" logo directly beneath the picture of the book cover. If you check the page for Lover At Last you'll see that logo is not there. It's not Barnes & Noble's choice. It's entirely up to the publishers to decide which books they will allow to be lent and which ones they won't.
07-17-2013 08:19 PM
The other books used to be. If your books still have the logo on your nook, you should likely re-register it. That will update all of your book listings. If the publisher has revised it, it should update to the new version. Not updating won't make a difference on whether you can lend though, you'll just get an error message.
About a year and a half, maybe 2 years ago Kindle came out with a book lending program. At that time 6 major publishers discontinued their participation in the B&N LendMe program.