Kingdom Hearts II is a good game, just not the best in the series.
Gameplay: This game introduces a few new features to the franchise. First of all, there is a new thing called "Reaction Commands". When a triangle appears, you press triangle. Its fairly simple, and works fine. Also, you can now fuse with one or two of your allies to become more powerful. This is called a "Drive". This is also fine, but it makes the game even easier. My experience with this game is one thing: Sore thumbs. Obviously, this game contains major button mashing. Its okay, but it doesn't help with the tedium factor. This game's is way too easy, also.
Story: This game takes place one year after Kingdom Hearts I and Chain of Memories. You play as Roxas, a new character, to learn how to play the game. Eventually, you control Sora, who has woken up from his long sleep. Then, you go on a long adventure through various Disney worlds, meet final fantasy characters, and battle the mysterious Organization XIII. Sadly, many of the Disney worlds don't have much to do with the overall storyline.
Music: This game features great music, different themes for the different worlds. I found myself humming along with the themes, because, sadly, there aren't that many tunes for the time you spend at a world. I especially loved the Organiztion XIII battle music. It is very catchy. Also, the game has very good voice acting. It still stands that this game has some of the best voice acting in a game, ever.
Graphics: The games graphics appear to be very improved over the first game's. The characters seem a bit smaller, even though all should be older. This is only noticeable in the gameplay, though.
Problems: This game has a few flaws, mostly in the difficulty. Thankfully, the camera is fixed from the first game. Sometimes, it still gets caught on things, but that happens very seldom. The one real problem that I had with this game, though, is it's difficulty. This game is way easier than the first game, and hardcore gamers should be able to breeze through the game in no time at all. Even the hardest difficulty mode is way too easy. Pity, if this game was harder, it could have gotten a 9.0 or 9.5. But, as it stands, it is truly an 8.5.
Overall: Kingdom Hearts II is a fine game. It fixes several problems from the first game, and creates a few new ones, too. I still found it fun, though. And, I suppose the overall experience is better than a few of its problematic parts.