This flash was pretty good length, and the graphics and style were pretty good, too. The sound was pretty good, and I liked the first 'play' button. You had a 'replay' buttno, too, which is a good thing.
Some of the animation got a little repetive, like in the guitar solo and when the fish was slamming against the glass. Also, mabye add a pre-loader, and have a music break...? Oh, and maybe you could improve mouth movements / graphics a little more...?