I will miss Misha so much if he leaves SPN it wouldn't even be funny, but, I'll admit I will probably still keep watching the show as long as Jared and Jensen are in it. Well, for at least another season. My attention flagged midway through season three and then Misha perked me up, so I reckon I could probably last through a season seven, but without Misha (or if either of Jared or Jensen leave), that's probably all I could last. :'(