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they sure make it easier. guess they were added in december. cool beans. good find. incorporating now.

hmmm... these events don't seem to work for all bosses (ie: RFC)

I can't remember when they added it but I have a few custom weakauras that use it b/c it's really handy when certain encounters start/end.
It probably only works for MoP onward. I haven't really checked it out, but I assume that's where a majority of the PvE points are going to be earned.