That's one of the worst of the lot for me. With Sheldon, they added so many mannerisms, such as germophobia, yet early on he was shaking hands with Gablehauser. I know it's only a small thing, but continuity errors bug me. And in the very first scene when they're going to 'donate sperm', how exactly was Sheldon going to do that? Then he tried to impress Penny in that episode, something he'd just never try to do. I'd say Leonard was the only one who hardly changed at all. Also when Raj starts drinking, would say that he has literally never spoken to a woman in his entire life. Season 2 onwards was much better though.