Nice. Too bad it's not fun.
Graphics: Mario sprite rips from various games with some editing. Everything looks lush and pretty.
Style: It's a class act all the way, from the colors to the controls to the physics. The selection of enemies doesn't seem to match the locale, though. Why are there skeletons at the beach?
Sound: Not bad. A nice soft Koopa's Beach remix with coin sounds ripped right from the games.
Violence: Light. Various mario enemies bonk, thwap, and bite you. Most of the time, you die because your boat got upset, not because an enemy actually hurt mario.
Interactivity: Surprisngly good. The controls work exactly like you'd expect them to, which is why it is so odd that the gameplay sucks ass. See Overall for more details.
Humor: Goofy mario antics. Silly face on the big orange blob thingy. Slapstick mayham when mario gets knocked out of the boat. No deliberate jokes, though, as far as I could tell.
Overall: I wanted to love this game. I *really* did. But the author made a lot of design decisions that totally fuck the gameplay over. I'm not talking about playcontrol, and I'm not talking about the coding. Both of those were rock solid. I'm talking about enemies appearing and hitting you before you could even possibly know they are there. I'm talking about coins and enemies appearing at random, so that more often than not, the coins overlap the enemies which means you can't safely collect them. The author needs to learn how to present challenges to the player that are not impossible. He needs to learn how to use random numbers to imply random events, without making the gameplay totally chaotic. We need to know what we're up against before it pops out of the water for the furst time and we die from it. And ideally, it would be nice if we had some sort of way of defending ourselves.
This is just my own opinion. The game seems to be doing very well, so I guess most people enjoyed it. I'm going to try it again and see if maybe there's a trick to playing it. But if you make another version of this, you might want to consider planning the placement of enemies and coins a little more carefully, at the very least.
And do a google search for articles on game design theory. The Carrot and the Stick, Risk VS Reward, stuff like that.
Good luck on your future games. Everything was great about this game escept for the gameplay. :(