Repetitive “talks” does seem to be a serious issue … with several (4 or 5?) WordCamps being very close at hand geographically I find it really disappointing to see the same speakers doing the same talks at each WordCamp (some within weeks of the other).
I think it would be great to have some way to promote and/or incentivize a diversity of topics/talks even if the speakers themselves appear to be the same group caravanning from one WordCamp to the next.