One really interesting aspect talking federation which gets obvious if you play around with different accounts on different services on different instances:It's hard to impossible to say how long it will take for a message, post, response, ... to make it to all the people you would like it to see. This feels very much more like the "timing behaviour" known from using e-mail and mailing lists than what people are familiar with (and used to seeing) with most of the current centralized proprietary platforms. It's obvious why that happens, but still I guess it'll need some work to make it both faster and ... more transparent, as in knowing whether a message, response, ... actually managed to reach all the systems it needs to reach.