Not sure what your intended purpose was for this to be, but it works fine as a sort of recommendation of songs for people to DL. One thing I would suggest is cutting the silence between clips, using cross-fade. I don't know if IMovie lets you do that, I use a program called Audacity to make mixes, but it's probably beyond what you want to do technical-wise.
Some good songs Btw
PowderHound and TreeNinja