Depends on what you mean by good or bad. People are just excited that Sasuke has chosen to do a good deed. He has never been Evil but has been good at one point in time. If he chooses to fight Naruto to the death, does that really make him bad? No. It's what he feels he has to do. However, that's only if Naruto agrees to their fight. If he just goes at Naruto with the intention to kill, then that's a different story, but I don't see Sasuke doing that.
I'm getting rather tired of the SasuKarin bullcrap though. Not sure why so many people want to see him with THAT.