I honestly don't see how a social network can survive without retweets. They're just not going to get the critical mass. There needs to be an "amplify" gesture and quote ain't it.
Disagree :) The thing that's breaking other social media is that the social part is getting removed.
Forcing you to write words and actually come up with an opinion instead of pressing a "repost" button without any context provides a much richer social experience.