It would probably work like an IRC network. A network might involve hundreds of servers, but you only notice which server another person is using when there's a

It would probably work like an IRC network. A network might involve hundreds of servers, but you only notice which server another person is using when there's a netsplit. Split users can reconnect using another server and rejoin the channel with only a slight interruption. An IRC-styled Twitter would need some sort of synchronization service to handle twitsplits.