I own both. SOT was infinitely better in terms of tone and story.
WW added some decent innovations in fighting, and the gameplay was quite a bit longer than SOT. But I didn’t really care about finishing WW all that much, where getting to the end of SOT was downright compulsive (although ultimately disappointing when the story did a Star Trek-style reset-button).
It really came down to the character and tone in WW v SOT: the Prince and Ferrah in SOT were characters you could care about, and you wanted to see what happened to them. In SOT, we get to hear the Prince’s internal, sometimes immature or selfish, dialog about what’s happening and what he thinks about things as the story progresses. We get some actual character development going, and it was pretty good.
The Prince in WW is a foul mouthed snotty bastard. Character development is minimal – his motivation is to not die, which doesn’t change, and he doesn’t evolve. In WW, his first real comment to another character is “you BITCH!” How charming.
I really didn’t care for the heavier sound track in WW. SOT’s was lighter and stayed out of the way, but was there enough to be mostly atmospheric and give a persian tone to things. WW’s music was, well, not quite metal, but harder than I’d care for. Not much variation from three chord heavy rock, it didn’t add much beyond: “ooh, tough fight, let’s crank up the guitar”.
Graphics were meh in WW – very dark. The character models looked like hell, especially the Queen of Time, she looked awful. Farrah and Prince’s look in SOT had issues, but this, to me, was a big step backwards.
I’d probably still buy WW if I had to choose again – it’s rare to find combat+platforming that’s even halfway involving on the XBOX. But the game does have issues.
Speaking of combat+platforming, I’m currently making my way through God of War on PS2, which is big fun. Keep an eye out for it if you like that sort of thing.