Also very useful are http://www.hnreplies.com for emailing when someone replies to your comment and hnrss.org which can seach for any keywords when used with your RSS reader. I recommend Inoreader.
Oh haha, thanks for replying here! Funny enough, I didn't even receive a notification for this comment, although I think it's probably unrelated to the previous instances. In this particular case, I accidentally unsubscribed (speaking of which, it would be nice if the page asked for a confirmation before unsubscribing?), but after re-subscribing and verifying, I haven't received anything, so I suspect it's a glitch there. In previous instances (which come up every several weeks/few months), some notifications seem to go missing for a day or two -- if I get a chance I might report them from now on.