My guess is that it's never coming back or it would have been reinstated already. Further speculation: the lack of update notifications keeps flame wars to minimum because the immediacy of replies is gone. No more hot-tempered, knee jerk reactions.
Yeah, but it sucks when we are trying to find the post where we were having amicable discussions. No need to lump everyone together. Someone who is hot-tempered and looking for a fight is going to dig until they find their thread, whereas with a civil discussion, while pleasant, people probably will give up on quicker.
It's not just updates that are not working properly. Ever since I noticed that the updates weren't working, I also noticed that if I am on the forum and send a PM and get one back while I am still on the forum, the actual email notification doesn't come in until a few hours or a few days later.