ok I've listened to the mp3 and I'm gonna be really harsh (mainly because Canon Rock has been done to death on the net and it has to be really good to impress me)...
First thing I notice are the volume swells in the intro, they just sound terrible, the notes are cut short and this sounds really amateurish (I'm not saying ** amateurish on guitar...) just that the intro doesn't start the whole thing off well...
Second, I like that you've played it harmonyed throughout the song - that's quite cool! Although I'd like to hear more adventurous harmonies used (not just minor 3rd... how about some 4ths? maybe a 5th or 2
just a bit more than minor 3rding the whole song lol..)
Thirdly... the sweeps need definate work as I noticed in the vid... the tricky sweep at the start has been fudged which is dissappointing! :S if you harmonised that I would have been impressed....
Overall it's not bad... i'm not mad keen on the guitar tone though - but I don't know your setup so I can't comment further on this...
Anyway sorry to be so negative but as I said Canon Rock has been done so it needs to be better than this I'm afraid!!