I use this as a resource all the time, but may be 3-4 days before coming back to check messages - where if someone replied to a message I posted (or replied to) I'd check back right then in there. Even on sites I visit daily - I may only do it once a day, but if I was notified that my message was updated - I'd go back and read / reply much more often. So I disagree with what you're saying, but can certainly see your points / views.
Shawn