I saw maiden last night in Cardiff, my first gig (cue aww). I'd always been told maiden were really average live, so I was kind of expecting to be standing there all night like "wow, this wasn't worth it". To add to this, since buying the tickets, I had gone heavily off maiden.
However, the concert totally blew me away. The new album was good enough, then when they started with the oldies, the atmosphere turned totally electric.
Having said that, as I said above, it was my first gig, so I was bound to think it was awesome.
EDIT: oh yeah, crowd response to trivium was exceedingly bad, and I don't think they are really looking forward to the rest of the tour.
Some guy in the crowd: "**** OFF"
Lead singer: "Look if you don't ****ing like us, don't ****ing listen to us and **** off to the back."
Quite a bit of bottling was done =).