[giovannibajo1]

They should lift the 140 char limit for conversations (=sequence of alternating tweets that begin with mentions), after the first 2-3 messages. This would allow people to begin engaging intelligent discussions, while leaving the majority of tweets in anyone's timeline small and concise.

[mdaniel]

I believe that LinkedIn charges you a "conversation token" to send an email, but you get it back if the recipient replies. If we extend that mental model a little, a more conversational Twitter might make it so one could receive 2x the last character limit for every reply for that specific conversation.

I'm certain someone will illustrate with game theory how that system would do weird things in the context of a multi-person interaction.