Usbourne's That's Not My... series has been around for a good few years now, and though some of the titles are getting rather obscure (That's Not My Frog, for one!), they're still incredibly interesting for little people.
Excellent for learning about adjectives associated with touch, these feely books are bright enough to hold the attention of the incredibly young without feeling gimmicky. It's a personal thing, but I'm not a huge fan of books with flashing lights and sound effects - in my experience, people use them to cover poor writing.
Daughter likes these books because they're short and colourful - they don't require her fleeting attention for longer than a few minutes. I like them because whilst it's easy to show red in a book, or write the noises that animals make, touch has to be experienced before you can describe it. I know there are lots of feely books on the market, but as stated above, the range of these is simply so wide that you can cover just about every topic a child could come up with. The familiar layout across the topics is nice too - there's a neatness to it.