Closing Time casting spoilers

So, I haven't actually looked at the list for the casting spoilers for Closing Time. But... I was wondering if any of you out there has seen it and was floored or gaping at the computer screen with the cast list. I accidentally saw that( Spoilers! )

will be appearing in the episode, but I kind of figured that one... so I didn't think that was too spoilery.

So were there any other shocking cast appearances that I should avoid? Or is it kind of like, "If you've been watching the series, it won't be a surprise."

God, I hope that LJ cut worked out okay.