Conversations transfer short bits of information and the speech in each turn is called an utterance. Using conversations in works of fiction and in the online social medium Twitter, we found that the utterance length of conversations is getting shorter with time but adapts more strongly to the constraints of the communication medium. Regional variations of utterance lengths in the US suggest that the lengths are not directly influenced by location but by a demographic variable. Similar results were also found for the UK and Italy, which contradicts the popular notion that there is a North-South divide with respect to talkativeness in these countries. Although not definitive, our use of novel sources of conversations has given us a tantalising look into the dynamics of human conversations.