As I've mentioned many times here, I'm a big fan not just of kids music, but also of making music with kids. As in, families making music together. Not in any Partridge Family-like way, but just adults and kids singing and playing together.
We've got a basket of instruments we keep in our living room that we pull out a lot, along with the ukelele and (occasionally) my violin. I might be the only one in the family with any significant musical training, but even if we're just marching around the house in a musical parade, it's important to me that my kids see music-making as something they can do at any point in their lives. I could care less if they ever get paid for making music, but it would be nice if, assuming they become parents at some point, they don't feel at all self-conscious about singing songs and rockin' the egg shaker with their kids.
Having said all that, that basket of instruments we have is really dependent on rhythm instruments -- egg shakers, sticks, bells. So when First Act asked if I was interested in having our family test out some of their First Act Discovery line of instruments, I was ready...