I think he's actually shown more of his soft side this season than the last. I may be the only one to see that, but to me, he was 'worse' in Seasons Two and Three (definitely three). As I've said before, one episode isn't going to determine what Bloo will be like. He's not going to stop being a jerk, but we will see more of the affectionate side of him in the future, methinks.
Maybe, I'm biased over the issue, but that's the way I see it.