Much better than expected!
Graphics:
Obviously, the graphics are spectacular, especially for a Wii game. True, in a game this intense, there are several clipping issues and similar bugs, but nothing that interrupts gameplay or detracts from the visual experience. The pre-built levels are very well designed from an artistic standpoint; Final Destination in particular caught my eye with the breathtaking backgrounds.
My only real complaint is the custom level creation parts. Very few pieces are given, making all custom levels look rather bland. Apart from this, the graphics are great!
Sound:
Wow. 300+ tracks. That's certainly going to be a hit or miss. Fortunately for me and all other Smash Brothers players out there, it was a hit. The soundtrack is very well designed, featuring all of the best songs from the various characters games. The preview of the Metal Gear Solid 4 soundtrack was an interesting inclusion, but it fits the part perfectly in the Shadow Moses Island level. Overall, the sound is very well done.
Gameplay:
Ah, this is where it gets really important. Does Super Smash Brothers Brawl stand up to its franchise title? I'm happy to say that it is indeed a worthy follow-up to Melee, featuring crazy and spontaneous character-smashing madness. The new Havoc engine successfully manages to handle the Smash Brothers Situation, and adds many new features, such as picking up items on the run. My major complaint here is the online play. While Wii games have never been known for online play, SSBB does a particularly bad job of things. You can either play directly against a friend using their Wii friend code, or join a random battle with random people. With this aside, and while there are a few minor bugs, overall the gameplay is very well done.
Story:
This is perhaps the first Smash Brothers game able to have this category in the review; the new Deep Space Embassy mode is a more in-depth version of Melee's adventure mode, with a story to boot. While it is true that the story is a bit shallow and confusing at times, people don't play Super Smash Brothers to experience an in-depth, life-changing story. The story is good enough to fit in well enough with the game, and that's what's important.
While it has a few small shortcomings, Super Smash Brothers Brawl is indeed an excellent game, and one worth buying, especially if you enjoy multiplayer experiences.