Similar to Sonos grouping, the ability to send content to more than one Airplay device at the same time is a planned near-term feature, yes.
awesome product that continues to impress and improve.
Is this feature working yet? I see multiple Airplay speakers in the iTunes remote, but I can select only one of them. In my configuration I have a “Party” mode (in conjunction with a Niles ZR6) where I want to stream to both an Airport Express and an AppleTV. If I use the Apple Remote I can select both destinations (in addition to the Computer on which iTunes is running). But in Roomie it appears I can select only one source.
This is part of the forthcoming Roomie 1.7 release.