Like Facebook does (and no, the suggestion is not about turning SO into facebook) I'd like to see a notification in the recent activity tab when there is a new comment to a post I previously posted a comment to, this way I can follow up.
Currently there's no easy way to see it other than go to the recent tab and manually check every post you commented on.
Normally, you only get notified of comments when you own the post.
You will now get notified of any comments that refer to you by @username in a comment, even if you do not own the post.
Only applies to other people in the comments that you are commenting on.
Response must include @username that you are referring to, where "username" is a reasonable match to the user's current display name (as seen in the comments above yours).
There must be a starts-with, case insensitive match of at least THREE characters to the displayname. So @a and @ab will never match anyone or anything.
Spaces cannot be used to match, so if the person's display name is "Peter Smith" then just use @peter to match.
Matching is performed in reverse chronological order, so if there are five people named "John" in the comments, writing "hey @john, have you considered apples?" will match the most recent John to comment.