Hi.
MusicBee's Keyword Tagging over Last.Fm support is really amazing. I'm long time searching for a Music Player that supports advanced auto-tagging, and MusicBee's feature and general quality seems to have a stop to my quest

But, i think Keyword tagging needs some advanced features, like Tag Filters, so we can tag songs in our custom fields (in Id3v2, of course =).
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Let me show you an example:
Song: Quinn the Eskimo (The Mighty Quinn) - Bob Dylan
Last.Fm tag results:
folk, singer-songwriter, rock, classic rock, Bob Dylan, folk rock, 70s, folk-rock, 60s, classic, oldies, great lyrics, Dylan, Birthday, beautiful, forever young, sad, Love, favourite songs of all time, Uplifting, positive, Ballad, Sentimental, male vocalists, favorites, hippie, folkrock, pop, acoustic, Mellow
(there's sh**load of useless tags in there, you see. i already know that's a folk song.)
What I Need:
Mood (Custom Field): Uplifting; Sentimental; Positive; Mellow
To achieve that, i might use a custom tag list, like
Mood: angry, bewildered, bouncy, calm, cheerful, chill, crazy, crushed, depressed, dramatic, drunk, eclectic (...)
or
Occasion: birthday, breakup, carnival, chillout, christmas, death, drinking, driving, hanging out, heartache, holiday (...)
or
Category: animal songs, autumn, b-side, ballad, banjo, bass, beautiful, bootlegs, brass, chamber music, clarinet, classic, classic tunes, compilations, covers (...)
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And then, MusicBee will be an amazing Media Player for people who love to organize and tidy up their archives, like Radio DJ's

Inb4, "use exclude tags"; that's only for "Genre" field.