Hmm.
The artwork for this game is quite nice, I like the style of it.
The only thing I can say is that I found it a bit awkward to jump with space and had difficulty getting used to it- maybe it's just me. But this made it difficult for me to stay alive in the game because I would forget to jump, not get the timing right because of it, etc. So, I didn't get very far enough in the game to really judge it, unfortunately. But from what I could see, it seems good, so well done.
Well..
It's a fun little game and overall cute, but one problem I had (that wouldn't let me past the 4th stage, so I had to quit) was that my shooting never worked in the stages. It only worked during the tutorial, so when I got to the "Kill 50 enemies" level, I couldn't advance beyond it, which is why I lowered the score. Also, something that bugs me ever-so-slightly is when I move my mouse too fast and the jellyfish kinda...lags behind, but that's kind of minor to me. Eh.
If I'm not the only one who experienced this problem, when you fix it I'll give the game another go. If I -am- the only one, however...well, it was fun for the first few levels.
For the lag you mention, the jellyfish is supposed to be slow. If you want to increase the speed, you can buy the speed upgrade, on level selection / upgrade screen. And for difficulties people respond were mixed, but I lowered it in the next update if people said too hard. Thanks..
Female
Fish Student
Fish
Joined on 3/27/10
Dr. Bones' Adventure 
Jelly Panic