As a business owner I would never sell an unsupported anything to a client without some written and signed paperwork to cover my ass. Additionally we have a clause in our contract and warranty statement that says we are not responsible for what third-party service providers do. Every vendor has told every dealer for the past 10 years that Sonos is not willing to support integration. Dealers said screw that, I'm gonna do it anyway. Now they're upset because they made a bad business decision. It's the same with guys controlling AppleTVs using IP. Eventually it's going to stop working. In Sonos' case it will be in April for all unsupported integration.

So back to Julie's original question...
We have never integrated Sonos with a control system. We have always used either Autonomic or Fusion depending on the platform. Sonos, although it doesn't make us a whole lot of money, is an option for clients being budget conscious. For us, we view the Sonos as a great music source for entry level systems. So now when I do a 4 zone Crestron system, my music server isn't half the cost of the entire system. Moreover, I now have a complete Crestron foundation installed in said customer's house ready to support future add-ons.

As stated above, the current functionality of the supported API is sufficient for today's generation of buyers. These are clients who don't own music...they stream it. Twenty favorites for most people is more than enough. I have about 60 Pandora stations, but only listen to about 5 of them. I have the entire SiriusXM service available, but I only listen to 3 channels. There's only 2 local radio stations I listen to. So the twenty favorite limit isn't a big deal. If it is, that's why Crestron let's you jump back and forth into the Sonos app on the new touchpanels, iOS and Android. If your customer has a large CD collection or iTunes library, or if you now have a personal vendetta against Sonos, then sell them a real music server solution.