I thought Uncharted 2 had a really average story and was impressed with it. But I still thought it worked well because of the humor and incredible voice acting. The top notch character models didnt hurt either.
But when you look at a game with a truly great story Mass Effect stands out as the undisputed champion. The scene where Shepard talks with Sovereign for the first time was the most gripping story telling I had ever seen in a video game after 25 years of playing them. And then they went and topped it in the same game when you meet Vigil on Ilos.
As for crappy storyline what you gonna do? Video games are still on the level of B movies in terms of story, but they sell well regardless. So why would developers bother tweaking a formula that already works. Very few try, and even fewer succeed.
