Bungie has stated they want to support clans (as in a playlist), but I don't think anything was announced. Not much known about faction, but I would not be suprised. Something of interest is the old menu option "faction wars". This may be an early version name of crucible, but it does suggest some kind of interaction past words. I don't know how it will work given that you don't "pick" a faction. Factions are just level bars, you can support them all. The one that gets the most support will have an advantage in Destiny sequels