I think I said this on the Redeemed forums, but the lore about the pandas really doesn't change anything for me. When they first appeared in WC3 they looked like a joke to me and they have been involved in more jokes since then. They just don't come across seriously, and one of the most important things to me about WoW is that it has tried to give you epic and serious expansions thus far. Regardless of how serious the story surrounding the pandas may be, the characters themselves are far too cute for me to be able to take seriously. Focusing a whole expansion on that is really making me less interested in WoW and even more hopeful that TOR turns out good.