Well, CC didn't fare so well in Game Informer. The game recieved a square of text of about 50 words jammed together with other poor games.
It got a 2. Out of 10.
"Just when you thought the updates and lack of people online couldn't make PlanetSide any worse, SOE drops perhaps its biggest turd in history; Core Combat. Featuring modules that can upgrade bases topside, a paltry list of new weapons and vehicles, and some amazingly boring underground labryinths to fight in, this expansion has hurt the game more than it has helped. Perhaps Sony should have looked at fixing the problems with the original which charges a monthly fee, rather than ripping off its player base with anoth $30 for this pathetic expansion."
Harsh. To put it into perspective, GI gave Grabbed by the Ghoulies for Xbox a 4.