I saw it too. In the actual pilot, Leonard said "Oh come on, you're almost a pro!"
Leonard do say ''You're a semi-pro'' in the actual Pilot, thought. Sheldon wasn't made completely asexual until after the Pilot! Luckily, there weren't enought sexual references for Sheldon in the actual Pilot so that making him asexual was unbelievable... while, like some said, he did have sex in the unaired pilot!
That kinda ruined any potential for the Sheldon we know, it would have went a completely different direction!
Back on topic, thought, I think the main difference between the unaired pilot and the actual one are the characters they brought in, aka Penny+Howard+Raj VS Kathy+Gilda. I mean, many of the same jokes do come back in both versions. So if I compare both version's characters then, yes, Kathy was very bitchy and unlikeable; it's very good they changed it for the sweeter Penny we know! On the other hand, I do like they geeky girl/friend, Gilda, she was kinda cool and all! I mean, I do like Howard and Raj, like everyone else, but I'm just guessing they could ALSO have kept Gilda around, she was a good representative of the female geekdom! 'could have been nice, but we'll never know! Anyway, yeah, Kathy out, Penny in! :D haha