If you guys were renovating a home and had a few rooms in which you wanted to play your music, what would you do?

A friend asked for some advice for just such a thing. He's working on a couple rooms and wants audio in a third. It seems that the preference is for something embedded in the walls/ceiling, and not something sitting on a counter. It's possible that putting equipment somewhere central would be acceptable, as long as it were built into something to hide it.

Naturally, my mind jumped immediately to Sonos, but is that the best solution here? How do you work Sonos into in-ceiling speakers? What speakers would you use for the purpose? Is there another system that would work well for this?