I have to ask...
...were you drinking when you made the victory/loss messages? If not, you fake it well. ;)
Anyway, review:
Graphics: Were awesome. I loved the fact that that sharks dissolved into blood when panched. >:D Also, the backgrounds were actually designed much better than any of these other rhythm-based games, where most of the focus is directed to the action. Good job. :D
Style: The name says it all:
SUPER VIKING SHARK PANCH CORPSE RIDE MEGA EXTREME 9000
Plus the whole aggressive viking narrator type thing was pretty cool.
Sound: The songs you picked were awesome, and the victory/loss/begin messages were priceless. XD
Violence: Do I really need to explain? 10/10
Interactivity: The only real problem I have with the controls were that there were so few. Why isn't there a button at 100% energy to call in the wrath of Odin and his hammer and laserbeams? I took off 2 points, one for the lack of Odin-ness and one for the lack of the 'pew-pew!'.
Humor: This gets a 10/10 solely for the 'Author's Comments'. And the name. And most of the game. You get the idea.
All-in-all, definitely one of the best games I've seen on NG. Make more!