Has anyone seen Metal Evolution? Done by Sam Dunn, the same guy that did Headbanger's Journey, Global Metal and Iron Maiden & Rush documentaries? It's a series of 11 episodes, covering the evolution of metal or something like that. Episodes are pre-metal, early metal in UK and US, NWBHM, glam, thrash, grunge, nu, shock rock, power & prog.
Surely some strange decisions up there about what's included and what left out, but generally I find it very well made and quite informative, especially when he touched topics I'm not that familiar with - like nu metal and early US metal.
When he's talking about power metal, he goes to Slovenia (MC) and proclaims Metal Camp a power metal festival
Some might argue A LOT about that, but I can forgive him