Upstream you wrote that iMessage is better than … in multiple dimensions. I've never used iMessage and am chronically curious. I understand from your comments a

Upstream you wrote that iMessage is better than … in multiple dimensions. I've never used iMessage and am chronically curious. I understand from your comments and those of others that the UI is one such dimension, even if opinions vary (don't they always). Could you elaborate on what makes iMessage better other than the user interface?