Simply put: yes, the game is different from the first two. It's more modern, the graphics are far superior, but it's lost the giant scale of prior levels and the animations are more stilted. It doesn't matter. Although smaller, the levels are far denser than anything in the other games (which tended to be vast, but minimalist and empty). A few inconsequential details have changed, but overall the entire trilogy is still one of the best series ever created and each game is incredibly immersive. Do yourself a favor, make sure you apply the "John P. high res texture pack" before you play - the game will look nearly as good as any modern release.
