Most days we average reading 3 times per day. We have gone through 40-50 books in one sitting. Some were really short though. A typical reading is around 20. There are about 50 books in her "familiar and favorite" basket, and I try to read new ones too. She loves to read about insects, animals, and apples. She does have some that she loves to read over and over, and she really has to be in the mood to read "new" books, but I can usually sneak them in between her usual ones.
Today we read books twice, not including the book I read to her when she was in her crib ready to go to sleep. Strangly enough she has been requesting this, and usually ends up sleeping with that last book at night in her crib. It has become a new routine.
It occurred to me after the first reading that it might be interesting to keep track of the books we read today and take a picture of them. With that in mind I set aside all of the first round of books and added to the pile after reading again. Most of her books I only read once today, although there were a couple of exceptions. Today we read 37 different books, not counting the crib book or the ones she "read" in the car today by herself.