Part of the documents have this to say about the Nexus Q:
The following paragraphs only apply if you purchase a Nexus Q.
You understand that the Nexus Q currently supports only Google Play Music; Google Play Movies and TV; and YouTube, and that your use of those services is subject to the Google Play Terms of Service.
The Nexus Q has built-in Wi-Fi and a built-in ethernet controller. You are solely responsible for obtaining internet connectivity through an internet service provider as the Nexus Q does not support mobile connectivity.
In order to use the Nexus Q, you understand that you will need your own: (i) phone or tablet running Android 2.3 (Gingerbread) or higher with access to Google Play; (ii) compatible speakers, AV system or HD TV; and (iii) 802.11a/b/g/n access point Wi-Fi router.
Update: Google has released a promo video of the Nexus Q: