Notifications

I'm just beginning to look at turning off "site notifications" and have noticed that the new 1.8 elgg website has then removed. If it's such a good idea why can't this option be part of the core plugin?

Also I think it wouldd be even better to "Follow" a particular Discussion, so that I receive Notifications about a subject that interests me rather than from the all of that group. I currently have to check back on lots of Bookmarks to see if any updates have occurred which is quicker than trawlling through hundreds of emails, after a few days away.