A lot of Music Industry 2.0 involves interacting with your audience one way or another, more than just relying on the old 20th century recording industry to hype your wares (or their wares, if you make such a deal).  The most efficient way to do that is by pulling off a kick ass show.  In my opinion, and at the risk of stating the obvious, here are the major elements that make a great concert:

1. Good band.  Duh.
2. Good crowd.  Duh.
3. Good bootleg recording, so that you can relive the good band interacting with a good, reciprocating crowd.  A concert video is great, but unless you’re the camera person, those edited angles aren’t your point of view.  A tape, CD, or mp3-set of the show is a good way to time travel.

As icing on the cake -

4. Good concert poster.  Concert poster creation really is a parallel art form.  Other than the name(s) of the band(s) on the bill, the date, and the venue – the imagery really has no obvious connection to the show.  Strangely enough, not connecting – in my opinion – totally connects, and a good poster is like a trophy souvenir of a great show.