Dan Moren reports that Twitter is rolling out their algorithmic timeline, where tweets aren’t strictly reverse-chronological. It is opt-in for now, and likely won’t apply to third-party clients:
"I’d also guess that third-party clients won’t be able to implement this for a while, if ever. So users of Tweetbot, Twitterrific, and others won’t really have a substantively different experience."
I don’t see the setting in my Twitter account yet. As a user, I hardly care, because I don’t read the Twitter timeline directly anyway. But I’ll be watching how people react to this and how it might affect my own microblogging plans.