For those of you who don't, here is the current status concerning comments not being received by email:
This is an update on the current condition of your comment notifications that you may not have been receiving in the last couple of weeks. The good news is we believe we have found the problem and we're working through the back log of email to be delivered. The bad news is that it took us this long to find and fix the problem - and for this we sincerely apologize.
Since our data center move last month, we've been tackling a number of different issues with regard to email. When we changed the IP address for livejournal.com we were put on a number of popular spam blacklists as a potential spammer. This caused not only email from us to be blocked, but also more stress on our mail systems trying to resend all the blocked email. When our mail servers become slower to respond, we queue mail in databases to be sent at a later date. Once these queues became too large, however, our system to retrieve the mail and send at a later date also became too slow.
We believe we've now found all the blockages for mail and over the next day you will be receiving the backlog of mail not delivered in the last couple of weeks. If you are still having any issues receiving email after the next day or so, please do open a support request.
Thank you for your patience and understanding.
So fingers crossed it has been sorted this time. I'm sure everyone - users and LJ staff (who are users too of course) - will be very relieved. If a support request does need to be opened it can be done here.