I like Rey Mysterio and think he's a great and entertaining wrestler. The problem is he strikes me as being too damn small to be holding a Heavyweight Championship Belt. Every time he gets into the ring with some big bugger it looks like he's going to get the snot kicked out of him. I kept waiting for JBL to yell "I"M BIGGER THAN YOU, GET IN MY BELLY" ala Austin Powers.
But Mysterio has paid his dues, and I don't begrudge him having a title run. He'd been in the business a long time. However, I think once he's had a few more monthes, Benoit, Booker T or most likely Batista when he comes back would be more realistic champions considering that Smackdown has alot of huge freaks running around on it.