Does anyone have any information about the Season Finale?

Well then wait until May 13, 2010!

Kidding, I have some spoilers for ya:
***********WARNING, SPOILER ALERT***************
So, all I know is that Michael appears and there is a fight with Castiel and it ends badly for him. Before you go all ‘Deer caught in the headlights’ on me that does NOT mean automatic death for our Angel of Thursday. It could mean, he becomes a fallen angel, or he reverts back to being Jimmy. Or, another possibility, he get’s sent somewhere, and we won’t know where until season 6’s premier. And yes, there will be a MAJOR cliffhanger, I think. Hope that helped.

go on wikipedia