Yes, MW2's MP rewarded good "twitch" players while COD4 and BO reward map control and enemy engagement. You could try to control your engagements in MW2, but if you didn't have the twitch skills to go with it, all your careful planning could go out the window at the drop of a hat - and it usually did. Throw in the constant carnage raining down from the skies, and you didn't have a very serious shooter.
BO has less "randomness". This is due to better map design (MW2's maps lacked flow; BO's maps has it for the most part), much less emphasis on killstreaks (which has already reduced camping), and perks that are insanely well-balanced. All around, it's a slower more "deliberate" game.
I noticed there wasnt a barrage of artillery from the sky but figured it was because no one had reached a high enough level to drop nukes. BLOPS doesnt have that kind of thing at all? I did see radio controlled cars with C4 and, stupidly, stared right at it as it drove up to me ("awww how cute! hi little fella." <BOOM>)
I'm fairly unexperienced with this type of MP so some of the perks/power-ups are new to me. For instance, it took me a little while to notice I had a spy play available to me that reveals the location of enemies. The first time I used it I felt so ditry--like I was cheating or something.
There is just a LOT going on in the UI for newbies like me. Still, I think I did fairly well.
One of the things I like are the contracts. I only went into the menu twice, but I think the concept is cool. I dont fully understand it though, so here comes newbie quesiton #2: You purchase a contract with something and then it rewards you with something? Is there two forms of currency in BLOPS?