Seriously, there's not a single titan in the whole show! I know, I know, it sounds cooler...
Clash of the Titans was a fun movie, and if you want to see it at all you should definitely see it on the big screen. Liam Neeson rocks and Hades, though evil, was way cool. The witches were spot on, and though they might seem reminiscent of Pan's Labyrinth, the eye thing IS originally from the myth. I did like some of the interpretations, and I know that Greek mythology by its very nature allows for tweaking, but:

Io shouldn't be in this movie at all. I could go into her story, but I'll save it for another time.
What happened to Hermes' winged sandals? Alright, alright, that would have been a little weird for a movie... and where are the other Gorgons, Medusa's sisters?

And pray tell, what is up with the ending? He defeats the bad guy, makes up with daddy and gets the girl...the wrong girl! Like I said, Io doesn't have a thing to do with Perseus in the old story, and throughout the movie I was getting an idea of good friend/sister/guardian/teacher...not love interest! Sure, the actress is beautiful. Sure, Andromeda has a small part in the movie. But everybody knows the age old deal: You save the princess, you marry the princess. End of story. Doggone screenwriters.

So if you're a Greek mythology nerd/purist, don't see this movie. It will only irritate you. If you don't care that much and you like giant scorpions and cool effects, it's worth it. If you don't have anything better to do and want to do something fun (like me), might as well.
That's my opinion anyhow.