If I might add another reason to have a "Pending Message" notification:
I am currently a member of 6 groups, 3 that fall into the general subset that this one does.
Now, granted, most people's memory is probably much better than mine, but:
"Which group did I post that to?"
"Did I post to the right one?"
"Did I post?
are all questions i have asked myself.
The last one actually comes up more often than you might think because not all Moderators are as Johnny-on-the-spot as the Moderators of this group.