Review from a competitive COD player since 2003..
The story is one of the best in the series, and the series has been known for a cinematic single player campaign of "holy s*!t" moments. However, Treyarch tries a little too hard with the cinematics which makes the game feel too fast. The constant bombardments and things blowing really become stale. Don't get me wrong, I love to see a good explosion and yell "holy s*!t" myself. Treyarch just never went for the balance. Infinity Ward has always been great at pacing their single player to create a lot of incredible moments when you least expect it. While the story is great, the pacing is terrible which makes even the biggest explosions just not even matter near the end of the story. Oh... and by the way, the AI is terrible as always.
Combat Training is a new feature for the COD franchise, but Killzone implemented this into its series a while ago. Its a fun little quirk to the game, but having to play a single player challenge while needing to be connected online can be a hassle.. especially when the servers are acting up.
The multiplayer is just how you would expect it from a game that is a port from MW2... its all flash but no substance. The currency system is a nice change, but it isn't anything ground-breaking in the genre. The game still feels like an arcade shooter where people just run around and spray. While perks, killsteaks, deathstreaks, and other new features might bring sales up, it deprives the game from truly being great at what its suppose to be: a shooter. The guns have little to no recoil, and you hardly accuracy skill to mow down your enemies. The maps in multiplayer are also lacking in variety. It seems like everything is a torn down street for the exception of one map.
Zombies are back and it is the best part of this game. However, you need at least 2 other people to make this interesting. Even then, you are only getting a chopped down version of Left 4 Dead. If you need your zombie fix, you are better off getting either of those two games.
This game is all flash but no substance. Like MW2, the multiplayer is only good in short bursts.. short intervals. Because of its ridiculous random deaths and lack of skill required to play the game, it really just gets boring. Nothing feels new in the game. The guns mechanics, perks, currency, weapon customizations, maps, combat training, and gameplay are all old features and nothing ground-breaking. Therefore, it feels like you are just playing MW2 with slightly different guns.
If you still enjoy MW2, then you will definitely enjoy Black Ops. However, if you quickly tired from MW2, then don't expect Black Ops to be your FPS fix.
I gave this game a 7.5 because it is still fun to play for 30mins at a time.. but it just doesn't compete to other shooters already on the market that require more skill to master. Also, a game shouldn't receive a high score when its almost a carbon copy of another with added features from other series. 7.5 is a fair score.