Just my thoughts on Grenade Launchers in CoD.
One of the reasons that some think ruin the game. Grenade launchers are easy to use, but hard to master. Regardless of whether you use GL's excessively or not, you're still going to be called a noob tuber. Apparently only "noobs" use GL's; all other players avoid it thanks to crying from other players. Apparently, people do it all the time.
In CoD4 and WaW, equipping a GL sacrifices the Tier 1 Perk, and since many players refuse to give up said Perk, noob tubing is somewhat rare. Nevertheless, some dedicated servers ban GL's, and the ones that don't will have players whining after the rare GL kill.
In MW2, noob tubing is much more common, since equipping one no longer takes up the Tier 1 Perk. Thus we come to one of the many "problems" of MW2 because apparently all players noob tube. We also see complaining on the PC, such as "X is noob tubing," apparently wanting something done about it. While it is more common, I don't see a problem with it. On Team Deathmatch, Free For All, or Domination, I regularly gain AC-130s and Chopper Gunners, using either a sniper rifle or an assault rifle or SMG. Even where there are excessive tubers, I still can get my killstreaks.
In Black Ops, GL's most likely will not take up a Tier 1 Perk, since said perk determines the player's character's appearance. That doesn't mean that the launcher will take up a different Perk slot, equipment/special grenade slot, secondary weapon, or some other penalty.
Conclusion: There is no problem with noob tubes. Noobs use them excessively, while pros use them situationally (i.e. the target is a camper or behind cover), likely the intended use of them. I have a dedicated noob tube class in MW2, for fun. I don't see what the big problem of noob tubes are (apparently Thermal Scope requires no skill, even though you need to unlock it using the regular sniper scope and ACOG). GL's are easy to use at close range, but difficult to use at long range. Grenade Launchers are part of the game, get over it.