This is a great show because it can be watched in two ways: First, you can watch it with kids. That was the key to "Who Wants To Be A Millionaire?" and it works here as well. The kids love it, especially if the adults don't know the answer (it doesn't matter whether it's the adults on the screen or at home).
Second, this show is sufficiently predictable that, without kids around, you can watch it in ten minutes or less on TIVO. Do you think you're smarter than a 5th grader?