(Even thou it's a 64GB card it will have some reserved space to perform tasks and operation, usually you'll get 59/60GB, same thing with any card size 32GB cards you get around 28/29GB it's normal so don't be alarmed this, this is been around since first ever 1GB card was released)
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Isn't this because of the standards of HDD (and other media like SD cards) count a GB as 1000 MB while a computer uses 1024MB.
OK, used google for a more exact definition since I just woke up from 3 and a bit hours sleep.. My trusty 4yr old cried out as I was just drifting off at 3:25. Anyway, yawn and all that, check http://techforums.nintendo.com/thread/16722 and see beardedone's explanation.
(Oh, just saw dates. Seems I'm also a necro poster along with being a zombie this morning.....
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