In the accepted answer to that first question, Jeff quotes Joel Spolsky, who wrote:
I think we're all in agreement that in a social/discussion forum it's OK not to have email notifications, because in a social/discussion forum that's would be, well, antisocial.
But you know what? We're not all in agreement on that.
Instant email notifications (like those from Facebook, for example) increase engagement with the site-- they let you know immediately that a conversation you're part of has had activity, so you come back and re-engage with the conversation. Ultimately this increases site activity rather than decreasing it. I come to the trilogy sites when I have a question; I don't hang out here all the time. Usually when I'm done asking a question I hang around for a while and post answers and comments, or at least read. But then I leave, and nothing engages me with the site until the next time I have a question.
[I'm aware that RSS feeds are offered. Not interested. Doesn't fit in with how I use an RSS reader. This is about improving EMAIL notification.]
So here are my feature requests:
Allow users to select either immediate or daily batch notification on questions. Immediate notification allows me to engage when the conversation is fresh, not when it's two days old. If rate of notifications is a problem, throttle them (no more than 1 notification per user every 12 hours; after the first one you batch activity into digests as happens now). The problem isn't the batching; the problem is that for a relatively light user the conversation is stale by the time I return to the site.
Fix the UI for subscribing to questions. I've got "I'd like email notifications of activity on my questions and answers" checked off in my profile. Why then is the "Notify daily of any new answers" box unchecked by default at the question level? If I leave it unchecked, what is the behavior? The UI is unpredictable.
BUG: If I check the notify box on a question and then the question can't be posted due to a validation error, preserve my selection.
Broaden notifications on comment threads-- If I have participated in a comment thread, allow me to get notifications on it! It's not clear to me how this works now-- I think comment notifications are only sent to the poster of the answer or question being commented on, but I'm not clear on that.