No, if you can take advantage of the AppleTV box features, and need/want them, then there's no reason not to choose it for marginal cost increase from the AirPort devices, AFAIK. In my situation, I initially wasn't going to use the device with a system with a TV, only audio. And the apps that I'd probably use on AppleTV were available on my Xbox anyway.
iTunes currenly tells me that I could listen to my library for 27 days straight and not hear the same song twice. It's like having your own radio station with nothing but your favourites. And better sound quality.