Marmie was watching S yesterday while Phil and I went to pick up a vanity from the Home Depot Expo (that has a long and boring story behind it). We have two books right now that S seems to love, "Where's Spot?" and "Dear Zoo" both "lift-the flap" books (pictured here from penguin.com.au and from overstock.com in case you need childhood reminders).
After going through the spot book (where you open a clock, a piano, etc and look for Spot but instead find other animals), Marmie and S read the zoo book. One of the animals the zoo sends is a monkey. When Marmie and S got to the monkey, he paused, reached for the spot book and opened the up the page with the monkey on it (I don't remember what it's hiding behind). He then compared the two images. He recognized that they were both monkeys! He is so smart!
(And if you have a 10 month old, maybe even as young as 9 months old, I highly recommend flap books. These two are cardboard and have flaps, ideal for chewing and "reading.")