The Metal ArchivesLost Souls DomainBNR Metal PagesSatan Stole My TeddybearMetal ReviewMetal Rules!Metal CryptAmerican Nihilist Underground Society (ANUS).
Endless GriefThe
Metal Archives is the best for getting a nice neutral spread of opinions, I think. You can search by genre, country, album titles, lyrical themes etc. through a pretty comprehensive register of every metal band ever.
Lost Souls Domain is a similiar but less comprehensive service with slightly zippier dicography navigation (imo), and the
BNR Metal Pages again offer a similiar service, but with more comprehensive band biographies.
Satan Stole My Teddybear has a nice, comprehensive register of all sorts of alternative music reviews of the kind of stuff Pitchfork wouldn't touch with a barge pole.
Metal Reviews is a straight metal review site with a slightly odd rating system.
Metal Rules,
Metal Crypt and
ANUS are all decent review and editorial sites, but if you're new to metal take ANUS's editorials and views in particular with a pinch of salt: Anus is run by extremely pretentious black metal nihilists with a hint of nazism about them. Not that they don't say some valid stuff, but they are pretty quirky. They have a neo-classical section, but refuse to review the operatic Therion albums as sell-out, for example.
Endless Grief is just a nice little post-script, little subjective descriptions of a great slew of metal bands, with a doom bias, which helps to give you a bit of flavour.
What kind of metal are you looking for anyway?