Maybe we don’t have to choose between persistence and spontaneity, between synchronous and asynchronous.
Consider threaded blogs vs live chat. The former has a permanent record and structure, and people can collaborate asynchronously, but lacks spontaneous give and take. The latter is spontaneous, but lacks permanence (unless someone saves a transcript, and manages their collection of transcripts, and the sharing of same with others). But do these have to be different mechanisms? Maybe we can have everything with a single interface, so people don’t have to choose?