Small improvements. Don't get me wrong: the things you listed are all nice and useful (+1 for keeping more than one stack trace). But I don't think anyone's definitions of "innovation" includes fixing exception reporting and changing the semantics of object comparisons. No disrespect intended but your earlier statement was clearly meant to convey what a boatload of innovation there was in Python3, and your response to the request for an example just bolsters the counter claim, frankly.