A great genre of metal.
Doesn't matter how many people discard it at not metal, it truly is apart of metal history.
If anything, Nu-metal should be getting the criticism, this is how i see it.
Nu-metal is alienated from metal, musically, because it is based on alien musical influences, namely rap. Glam metal may have been "watered down" for commercial consumption, but it never pretended to fuse metal with anything. To change a Poison song into something that would be universally regarded as traditional heavy metal you need only speed it up, thicken the guitars, change the vocals and tweak the rhythms and such. To change a Korn song into traditional heavy metal you have to completely deconstruct it, and remove something fundamental to it--namely, the rap elements. There is thus a great musical difference between glam metal and Nu-metal.
So, For those who don't agree that glam metal is metal and prefer to call it rock music, I would suggest you are attempting to re-write history. Calling bands from this genre un-metal or unworthy would ruffle many feathers of longtime fans of metal that know glam metal does have it's place in metal.
Shout At The Devil By Motley Crue was Voted Number 9 On Rolling Stone's "Top 100 Metal Albums Of All Time"
Glam Metal Was The Most Dominant Genre Of Music In The 1980's