Before I was distracted, I was able to find out more about this Horde gathering. Sylvanas has summoned the leaders of the Horde and its allies. For what purpose, I cannot say.
We aren't in a position to strike her down--she is too well-protected. But perhaps we can learn something that will prove useful in the ongoing war.
Keep your head low and take a look. I'll keep an eye out for more guards.