I was 10 years old when the original came out, and I loved it. But now I cringe a bit when I watch it again, as the special effects are really bad and outdated. The remake would have been perfect if they had stuck to the spirit of the original, but updated those bad effects. The Medusa and Kraken sequences in the remake are spectacular, but I missed the Perseus/Andromeda/Calibos love triangle of the original. That was a major plot point of the original, and now it's completely gone, so now you've got Perseus heading out to see the Stygian witches after only about 30 minutes into the movie (this didn't happen in the original until over 75 minutes into it). To me, this makes the movie feel rushed, like the filmmakers are just moving it from one action sequence to another.
Still, it's not a total failure, it just could have been much, much better.