I thought it was a pretty cool game. The written dialogue of Jack didn't feel right. Jack didn't really talk much and when he did, it wasn't like how it was in the game. Then again, this is just my memory of the show.
Visually, I liked it. Some areas looked like it may have had the same tileset, just recoloured but it looked nice and fit the samurai jack theme. Music and sounds were nice.
I didn't really like the jumping in an angle to get to the other side. The clouds in the falling through the sky level didn't look right. The enemies were easy, all you have to do is not fight them head on and swing your sword while running in angle, making the last level really easy to just run through till the end. One other problem that I had was that the game didn't tell me how to attack during that part when the controls came up.
I honestly thought that the end would lead up to Aku being the final boss.
Overall, this game was well done and I liked it!