Keep in mind that this review is coming from someone who has never been good at fighting games. To start things off, Street Fighter 4 is an exceptional game. Everything from the art style to the gameplay. Personally, I can't stand 3D fighters, so I was very excited to find out that even though Street Fighter 4 is running on a 3D engine, the gameplay is 2D. I'm glad that Capcom decided to take this route instead of making another crappy 3D fighter. The art style is awesome! The game can look a little silly at times (like eyeballs popping out of characters heads when attacked), but it does not take away from the game in any way.
I was worried about how difficult Street Fighter 4 would be. Capcom is very good at making games that frustrate me, but this time they made it possible for newcomers to jump right in and be successful early on. I believe there are seven difficulty levels so everyone should be able to find one that suits them best. However if you are new to the Street Fighter series like I am, then you probably should not bother going online until you get plenty of practice. Otherwise you will become somebodies punching bag.
Overall, Street Fighter 4 is a great example of what all fighting games should be. If you enjoyed Super Street Fighter II or HD Remix, then this is a must buy for you. If you did not like those games, then at least give it a rent. Even I found a ton of enjoyment in this game.