There's not much more to be said for Black Ops. The game itself is great. Treyarch has done a great job at balancing guns, perks, and killstreaks, and their support for this game is what elevates it from a 3 star to a 4 star review. Some may consider this balancing boring, but it prevents any one gun from being overused (although the Famas enjoyed a nice 6 month reign before being nerfed).
On Xbox, many people still use Ghost and Ghost Pro, which can be annoying, but with the Blackbird killstreak, it's not that bad, since you can see everyone. Second chance is also annoying, but people use it at the expense of using Hacker or Ninja, so I often hear them well before they run into my claymore.
Unfortunately, the game's engine is terrible. Hit detection is "hit or miss". Sometimes, I'm superman and I can take all kinds of punishment before I die. Other times, I find myself shooting someone twenty times only to die when they turn around and shoot me once or twice. This has little to do with who has host.
Also, the DLC, to put it bluntly, is crap. A waste of money. Perhaps if all three DLCs were on sale for 15 bucks, it might have been worth it, but aside from a couple of maps like Hanger 18 and Stadium, I find myself voting to skip every other DLC map. And judging by the other people in those lobbies, others agree and vote to skip as well.