If you haven't gotten Black Ops yet.. don't.
Im a huge CoD fan, and a big fan of Treyarch as well after World at War, and how amazing of a game that was.
They took a huge dump with Black Ops though. After the luster of the maps wears off (which takes about a month), you really see just how flawed the game really is. Lag issues, host issues, hit marker issues, etc..
They released a broken game.. and still haven't fixed most of the major problems. Yet they're talking about a map pack already. Its unreal.
I had so much respect for Treyarch and it seems Activision has turned them into crap now as they did with Infinity Ward. Both Black Ops and MW2 were clearly released before they were finished.. and the results are games that could have been much more epic, leaving gamers unsatisfied.
I'd pick MW2 over Black Ops if i had a choice. I remember playing MW2 with a group of buddies, and we had games going like every single night until the release of Black Ops. It never got old, and it was always a fun time, even with the frustrations of noob tubes and a couple other cheap things about the game. We had about 20 people and always had enough online every night to be able to play as a full group for hours. EVERY SINGLE NIGHT.
Now with Black Ops, our group lasted about a month, and since then everyone has kinda gone their seperate ways and are playing different games now. Its been a HUGE let down. The gameplay simply doesn't have the replay value of MW2 or CoD 4.
I still enjoy playing it every now and then (mainly just hardcore), but its nothing close to what it should have been. Broken game. Don't waste your money. Wait until next year for MW3.
Edit: GT is Garbz410 if ya'll want to add me and play. I have Bad Company 2, MW2, CoD 4, and BO.