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I'd rather be emailed about new answers to a question I am interested in. I know I can have RSS come into my email client (Outlook), but I don't really use RSS for keeping up with stuff. Never got into it. Maybe Google is right, it's time to retire RSS?
It is great to be able to bookmark a question, as currently available. But following a question, without having to rely on RSS, is also useful. Each option clearly has its place: on Quora they can't simply bookmark a question without following it, and that has been causing problems for some of their users.
In Github, watching still allows them to get notifications for projects all the same, but now users had a new recourse to simply bookmark interesting projects.. Originally, only follow existed, they later added the option to simply bookmark a project.
Both Quora and Github notify users who follow a question via email. Why won't Stack Exchange do it?