Okay, confusion time.
I beleive there are 4 keyblade bearers/weilders.
Sora, Riku, BHK, and Mickey.
I think Riku is a key bearer because in Final Mix he is told, "you have the keyblade for this side."
Of course Sora is still the Keyblade master in my book.
Alright that's it, what do you think?