Nope! Not a chance either of these games bomb or are a huge drop off in quality from previous versions.
I figure that Uncharted 3 will go down to ~94% becuase of high expectations and the complete inability to maintain high scores like that long. Look at LittleBigPlanet 2, it was agreed by ALL reviewers that it was a huge leap forward for LBP, better in every way, yet it went from 94.5% down two percent to 92.5%. I see about the same going here. I figure the singleplayer will be on par to Uncharted 2, but the multiplayer to be a huge leap forward (seriously, looks amazing), but increased expectations mean it'll be a step down in review scores.
Gears of War 1 wasn't anything special, just a mediocre game with some good ideas, and it got 93%, whereas the sequel had all those same good ideas, but didn't fumble and instead did a really damn good job and got the same score. Left 4 Dead 2 was a much better game and yet got the same score. What I'm trying to say is that I expect Gears of War 3 to be even better than the excellent Gears of War 2, but the difference in scores will benegligible, keeping it in the 93% range.
Overall they'll both be REALLY damn close and I think Uncharted will come out on top when it comes to reviews, but Gears will do significantly more sales. Both series are damn good, though, and I think PS3 and 360 users will all have something awesome to look forward to, so in the end we all win.
My Console Library:
PS5, Switch, XSX
PS4, PS3, PS2, PS1, WiiU, Wii, GCN, N64 SNES, XBO, 360
3DS, DS, GBA, Vita, PSP, Android







