Not at that level yet, but concerned that when I get there, my small guild isn't going to have the chance to fail at some of the endgame content, and have a bloody great time doing so :)
As previous posters have said:
Activated Raids: No Problem. Bigger guilds have more people available to do what it takes to activate. So they do it more often, but available to all.
Timer Raids. Problem. Big guilds need to share, small guilds don't get a chance.
Solution.... hmm, let me think :)