He's only had little tastes before though, this time he took far too much so it would have more effect I guess. She must be very tasty! 
I can't remember if their blood had protection/healing qualities in the books though. He didn't burn in the sun so obviously something is going on. Not sure how I feel about them NOT doing the really bad thing from the book. There's a part of me that thinks it was fine, it was enough that he drained her, but I would have liked to have seen how they would handle the after effects of her attack from the book.
On the whole though that was a top notch episode, I am loving Jason this Season, he's really growing on me as a character. And the girl they have playing Debbie! I hate her just as much as I hated her character in the book so she is definitely doing something right!!