Well we found a pickup group for Molten Core last night, so we decided to give it a shot. Wow, you guys would not believe the difficulty of that raid instance. Even the first mobs are insanely hard and one in paticular can multiply to like 50 elites if you don't wipe them out quick enough.
Needless to say, it may be a while before we get a guild group going there. We'll definately need a competant allied guild for it.