When I mentally divide your photo into an equal tic-tac-toe grid, the intersecting points of interest fall into the sky and water. Also, the photo looks more pixelated compared to other entries in the challenge. It might have better impact if that sailboat was a bit higher and further into the photo. Good concept though.
oh man, a potentially good image hurt by a couple easy to fix things...First, it is hard to find a clean, sharp subject. The thing in the foreground (pier?) was my first thought since the boat is really blurred but it too lacks the sharpness and detail it could have. Maybe a different depth of field would have helped or something as simple as a tripod if you didn't use one.
Second, your colors are rather dull. If you can't adjust this in your camera there are ways to fix this with software, specifically I would adjust the contrast up a bit. A little less exposure (underexpose it) may have also helped this some too.
Lastly, it appears you may have had some issues with compressing it to fit the 150kb limit and ended up compressing it too much. In the left hand part of the sky you can really see some jpg compression artifacts, your image seems to be 17kb so you had a lot of room to play with. Always compress a little at a time. There have been many threads lately about how to compress images, check the forums or pm me if you need more help.