Hype Lists:
    http://www.metalstorm.net/events/new_releases.php?upcoming=1

    http://www.metal-archives.com/release/upcoming
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    Death metal archive:
    https://mega.co.nz/#!yckVHD7J!PqNd5mjtWuSD3Zf15R6CAlgTLhlKYwnSz9f1Ya6c3P0
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    Blogs:
    http://moonlightgate016.blogspot.com/ (Various Genres) [new releases]
    [ctrl + f friendly]

    http://v1.realmofmetal.org/ (Various Genres) [new releases]

    http://v1.realmofmetal.org/p/discographies.html [discographies]

    http://echoesofdemise-v11.blogspot.com/ (Various Genres) [new releases]

    http://mortuusinsomnis777.blogspot.com/ (Black Metal + subgenres) [new releases, discographies]
    [ctrl + f friendly]

    Note: all of these blogs could potentially get taken down, but usually return within a few days.
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    Other sites:
    http://metalarea.org/ (Various Genres) [new releases, discographies, rare/obscure albums]
    [the website is in Russian. registration required]

    http://alterportal.ru/ (Various Genres) [new releases, discographies]
    [the website is in Russian. metal can be found under both "metal" and "experimental"]
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