Not quite messaging and not quite a social network, Spaces is a "destination for when you want to share, and talk about what you're sharing," the app's Product Director Luke Wroblewski, told Mashable.
Users create "spaces," chat room-like message threads, and invite others to join with a link that can be opened in the app or on the web. Conversations within Spaces are centered around chunks of content like web links, YouTube videos and photos.