i think the main difference, at least for me, between someone spinning vinyl vs cd vs software is that from an audience standpoint, a person spinning vinyl has the appearance that they are doing more. they appear to have a more active involvement in their set, where as someone who spins on cd can do a whole set without ever changing a cd. someone with software just looks like they are clicking buttons on a computer. even if what they are doing is very complex, it doesnt appear that way to the audience. its about showmanship. a set can sound amazing on any medium, but if the DJ appears to be doing nothing much besides clicking with a mouse, it IMO, kills the energy in the room. vinyl feels more hands on when mixing, and it is much more entertaining to watch a great dj tear it up on vinyl as opposed to cd or software. just my opinions as a fan and a dj