For Carmack: Without his engines, we wouldn't have had Wolf3D, Doom, Quake, Quake 2, Quake 3 and eventually Doom 3, plus the games built on those engines. No Carmack means no Half-Life, Soldier of Fortune 1/2, Elite Force, MOHAA, Hexen, Heretic and all the mods that have been created for those games. He has sometimes DRAGGED the PC industry into the future, kicking and screaming, be demanding better driver support, etc. Also, whenever a new Id game drops, the scramble to upgrade PCs makes HW makers happy. (If you say you won't buy whatever it takes to run Doom 3 well, you're lying!)
Against Carmack: At 31, he makes a lot of older guys feel like total slackers. Bagged Anna Kang as the Missus. (Drat.)
For Romero: Was lucky enough to be standing next to some actually talented guys at the right time and scam people into thinking HE was the brains.
Against Romero: Ran Ion Storm-Dallas into the ground with extravagent spending and produced one of the worst games of all time after claiming he was gonna "make us his b*tch". Cash drain on parent Eidos led to the demise of Looking Glass Studios, makers of System Shock 2 and the Thief series.* He turned Stevie Case into a (willing) whore for his game, taking her around to events like E3 and parading her like Pam Anderson - "Hey, like her t*ts? Buy my game!" - the pinup in the Daikatana strat guide was a big hint as to how "good" the game wasn't gonna be.
* To whoever mentioned Deus Ex - Warren Spector created that game at Ion Storm's Austin studio, while Romero destroyed Dallas. Anachronix was supposedly a good game by Tom Hall, but the moment it was released, Eidos pulled the plug, so there were no patches (that I know of) and no Win2K support, so it was basically a wasted effort, thanks to Romero's stupidity.
Winner: John Carmack (by light CENTURIES!)