Tyrant, I meant Clash of the Titans rode off the success of Avatar being in 3D, as you suggested. Other than that, Avatar and Clash of the Titans are very different films, so I agree with you.
"Clash of the Titans" -- a remake of a cult-favorite film that was released in 1981 -- was originally not envisioned as a 3D film. But then James Cameron's "Avatar," which also starred Sam Worthington, set box-office records worldwide. The success was based in part on its 3D effects, and Warner Bros. announced the already-completed "Clash of the Titans" would be converted to 3D. "Avatar," however, was filmed using special 3D cameras."
http://movies.yahoo.com/feature/movie-talk...-titans-3D.html
As for Percy Jackson, I think Hades was still villainous, although not the main antagonist. He showed up at camp in his satanic form and demanded the lightning bolt from Percy. I'm just saying he was portrayed as more "evil" than he deserved.
To Sandy, yep, the underworld looked a lot like Dante's Inferno. There was no Cerberus, Elysium, or Fields of Asphodel.