Is there any particular reason that this hasn't been implemented as a feature? I mean given the alert system that is already in the system, it would seem like a trivial thing to include alerts and email alerts for moderation items and for smaller forums that do not have moderators active on the system all the time, it would be a tremendous benefit to get e-mail alerts.
I can't actually find a previous suggestion for it in the suggestions forum, so either it hasn't been formally suggested (or it's not using the terms I'd expect) or if it has been suggested, it hasn't garnered much interest.
I swear I brought this up...will have to look for a suggestion and make one if it's not there. This always bugged me too because I like to stay on top of things that go into the mod queue, especially when I'm having one of those busy days and I don't get to look at any forums. I thought I was just missing a setting somewhere.