I've always had a big soft spot for The Smittens from Burlington, Vermont, and I think a video like this one should make it clear why. They're sweet and fun, and most often very child friendly too. A long, long time ago (well, two years) I interviewed this band on my other blog, so if you're interested after watching this, go check it out.
This quote from that interview says a lot, I think: "Sometimes we will all be in the same room with whomever's singing or playing and we remind each other to sing with a love thought in our hearts - kind of like answering the telephone with a smile - to get the most sweet feeling into each track."
Libraries, books, cats and kids! What's not to like?