It depends on how it's used really.

Of course, we can't/shouldn't dictate how other people play, but if people use it, similar to Akimbos, like it's a primary weapon and not merely a back-up attachment/weapon for a situation, that's when it's really a noob tube. (A "proper" way being to use it to hit people you know are behind cover or clearing out a group of people in close proximity and such.)

I've seen people go so far as to either run around and shoot it at the first target(s) they see or camp in a corner and pop at people with it that run by, then after depleting their shots, kill themselves with a SMAW, Grenade, or C4 to respawn with a full 2 grenades/whatever based on weapon again and keep repeating throughout the match. Similar with the SMAW itself, M320, XM25, RPG-7, and such.

Or at least they just run into groups of enemies to kill as many as they can before inevitably dying in a suicide run.

I agree, Grenade Launchers almost require sniper rifle precision to get a kill (in fact, that's exactly how I use the XM-25).

I personally never had a problem with them. It seems IW gave in to that part of the community who actually believe there is room for skill (and that Grenade Launchers are 'skilless') in a game that has always and will always, revolve only around reaction time.