Atlantic Ocean is an excellent attempt of making a simple subject into an elegant photo. You've tried one of my favorite techniques - finding horizontal layers in nature. You have 5 distinct bands of color - creating a layering of colors. It's a great technique.
Sometimes, as we learn more and more about photography, we discover when to make images. At other times - we discover when NOT to attempt it. I'm afraid this is one of those times. Your shot was taken in terrible high-noon (or early afternoon) harsh lighting. No film or digitial process except maybe black and white can handle the number of f-stops required. Your highlights - the sun reflections on the water - are very over-exposed - and you've lost some detail in the waves as well.
I would bet if you went back to the same exact spot several hours later, you would be far more pleased with the result.
As others have noted - critics are sure to notice a tilted horizon - especially when there's a straight line involved like water or a flat field. The secret here is to use a tripod whenever you can, use grid lines in your viewfinder if you have them - and be extremely careful.
Even if you do end up with a crooked one, you can rotate and crop - even in DPC's basic editing scheme.
You may also want to try using a polarizer in shots like this to reduce some of the glare on the water and also pop out the white clouds from a blue sky. It works best when the sun is at a 90 degree angle to the film plane - but will also work at the angle here.
I suspect the reason it did not score as high as you'd like is that you entered it in the "extraordinary" challenge - which had a ton of great images. Not only that, the voters were really expecting to be totally "wowed".
So - keep shooting and sharing - you have a good eye and just need more experience. It should come quickly if you keep hangin' out here.
Um, that ocean is truly extraordinary. It's going down hill! Seriously, you might want to check your horizons really carefully in water images. But colors are nice and surf is beautiful.
I like the glisten on the water. The image lacks that little bit of something more to make it just right... there's a lot of water and nothing for me to rest my eye on
I tend to agree that oceans can be extraordinary things, but I don't think this image conveys a sense of that. The waves look to be the primary subject here, and there doesn't appear to be anything extraordinary about these.
Nothing real special about this photo. A polarizer would help the foam, but detract from the nice sparkles. Maybe a little level work to darken the sky and water?