I don't think Sasuke is that bad. People need to realize, that he's not going to be happy-go-lucky, like Naruto is. From the get-go, his only motive was to kill his brother, no matter how. It's simply not right to hate him because of that. I think he's matured too, in his own way. He did learn to care for his team-mates (see, him defending Naruto against Haku, and insisting on taking on Gaara, despite his weakened condition to give Naruto and Sakura time to run away.) But, Itachi has so much negative influence on him, he fell into fits of insecurity. I mean, how many times has Naruto felt like crap, because others acknowledged everybody, BUT him?

I mean, by that logic, people should hate Naruto for having so much empty bravado, and loudmouth.