I have to admit that Gears of War has the most outstanding graphics of any game this year, but I think when you take all the other factors that make a good game into account, that Resistance: Fall of Man for the PS3 is a superior title.
Both have great graphics, with GoW having a slight stylistic advantage. HOWEVER, I think Resistance has a much better storyline, better writing, better sound, and better gameplay. Gears of War's storyline is sketchy at best, and the dialogue between the characters is juvenile macho chest-thumping at its worst, and entirely lacking in imagination. I mean, c'mon, this is supposed to be another planet at some point far in the future, yet everyone comes across as current-day steroid-addicted jocks? This is about as completely berift of imagination as a storyline can get.
On the other hand, Resistance is consistent in it's use of alternate early 1950s earth, with the scenery, clothing, and dialogue fitting perfectly into the setting. The storyline is much more robust and well thought-out. It does start out seeming to be a Half-Life rip-off, with an alien race infecting and converting humans to more soldiers to fight for them, but it has some interesting twists and turns later on in the game that save it from seeing like a total copy.
Resistance also avoids the repetitive gameplay of Gears of War. 95% of GoW is the same style: jump from one point of cover to another while popping out occasionally to shoot at the enemy. The GoW enemy AI is good, and there are a couple welcome breaks to duck-and-cover, such as a couple vehicle-based sequences, and the Berserker section also servers as a great change-of-pace.
However, unlike GoW, Resistance is constantly changing its tone and pace. It starts out similar to GoW, with an emphasis on use of cover, but has a more Doom 3 / F.E.A.R. feel later in the game, when it goes more indoors. It gets enjoyable creepy, and managed to make me jump a couple times. Later on it shifts to some chaotic outdoor battles with dozens of enemy and friendly soldiers, with mortar shells flying, and more resembles WWII-based shooters. It's constantly shifting, and along with the well-done narration (although, can we PLEASE come up with something other than the all-male soldier game with single-female-as-narrator approach!??!) is compelling and fun consistently throughout the entire game.
Finally, unlike GoW, Resistance has an excellent selection of weapons, each having a unique feel and set of capabilities. Every single weapon has a reason to be used, unlike the rather generic and uninspired weapon selection in GoW.
After seeing all the gaming sites come in with GoW as Game of the Year I have to admit I'm in the minority here, but I think this just points out that when everyone says "It's the gameplay not the graphics", many of them are being more than a little disingenuous, because I think graphics is the ONLY area GoW is superior to Resistance, and that in almost any other measure of gameplay, Resistance is clearly the better game. In fact, I'd even go so far as to say it's now my all time favorite first-person-shooter, surpassing even Half-Life 2 (just by a hair) as my all-time favorite. This is a must-have game for all PS3 owners.