At times, Spider-Man 3 is downright pretty to look at.
Spider-Man 3 requires a Shader Model 3 videocard, and while the box states Radeon X1300 and GeForce 7300 as minimum examples, they are not really viable cards to run the game. In our testing, a NVIDIA GeForce 7600 GT was the cheapest card that could reach playable frame rates with everything set to minimum. Spider-Man 3 caps the frame rate at 30fps (most likely due to its Xbox 360 origins), and in practice if the rate dips much from that, things rapidly degenerate to an unplayable slideshow. With the 7600 GT or an ATI Radeon X1650 series card, you can get close to 30fps in most situations as long as all is set to minimum - no, the game doesn't really look like it should require such hardware; buildings get fairly ugly, you lose all of the shadows and you still only barely reach 30fps.
New York in all it's glory, everything at High.
Same with settings at Medium - differences are minor.
At low settings, buildings are much simpler with plain textures.
Hanging around at High settings, note the shadows and the amount of pedestrians.
Same at Medium, some detail and dynamic object shadows are gone.
At Low, the draw distance is cut, lighting is much simpler and environmental maps on the windows are gone.
We tried the game also on a range of NVIDIA GeForce 6 series boards - with a GeForce 6600 256MB the game was pretty much unplayable. It might just about run on low settings with 6600 GT if you bump down the resolution, but we can't recommend playing with first generation SM3.0 graphics cards.
To reach a playable framerate at high settings you need a lot faster system. Our ATI Radeon X1950XT was powerful enough at 1600x1200 for almost constant 30fps, and with a bit lower resolution, you can reach the same with our recommended setup. The CPU is fairly unimportant and almost anything goes in that regard. On the memory side, 1GB is enough if you run the game on XP while Vista asks for more - and in any case 2GB sure doesn't hurt.