This paper explores evidence from a large scale, mixed methods investigation into political conversation in various online niches, uncovering a model of deliberation in which shared cultural or social ties – non-political ties – seem to play an important role in holding a quorum together and encouraging exchange of diverse opinion without breakdown of the community. A shared sense of community identity is important within this model, but robust and stable individual identities – usually in the form of pseudonyms, but which sometimes translate to offline identities among sub-sections of the community – play an important role, too. These shared community spaces may offer democratic benefits by facilitating the testing of balkanised perspectives found within personalised digital media structures against diverse counter-perspectives.