Approving people in spaces takes a bit of time. It is so important to know that when you ask to join a wiki or Diigo group or grouped on Linked in that you let the person approving you KNOW why you want to join.
When You Don't
If you don't, you force the person approving to go through and look at your profile to determine if you are a spammer. Sure, a spammer can lie, but usually they just don't put why!
How to Get "Accepted"
If someone puts a message:
"Vicki, I heard about this group in a Diigo presentation you did at ISTE last year."
Image via WikipediaBANG they are approved immediately. But if they put nothing, I wait until I have time which is usually once a month for the Diigo educators group.
If you are upset that you're not getting approved to join things more quickly, maybe it is because you aren't identifying yourself and why you want to join. People who identify why they want to join a space are showing good citizenship and technology savvy and are the kind of people that are wanted in communities.
Teaching the Netiquette of Joining Spaces
When my students join the wikis for our projects, I require that they put a comment when they ask to join. This is good netiquette.
This is one reason why I don't set up wikis for professional development ahead of time - or at least I don't issue joining invitations. I WANT those in the room to see me approving and I want to mention specifically those who comment when they join and show how it looks on my end. I do this with my students so they will learn the netiquette of joining.