Well to be fair the trailer isn't quite new, but it has been reworked somewhat, particularly with the new soundtrack. In fact I'm really not sure how else it's been changed.

Can you see any tangible difference, or is it just the music soundtrack, and really, what difference does the soundtrack make to the trailer?

You can see the new trailer for Saw V here, re-released because there was a problem with the music. Well, I'm not sure that this one is any better. You can see the previous one right here on Filmstalker too.