People might know that its original and then again they might not. People that have only heard of hatsune miku will be still attracted to this thread because of that common misunderstanding. As far as I know, black rock shooter the song was created by Ryo, the main music artist in the band called Supercell that just got uber popular in Japan and one of the band members Huke who is in charge of illustrations along with other members drew or created the actual black rock shooter miku. The band used VOCALOIDS2 - Hatsune Miku to make songs before, and are responsible for Black Rock Shooter and other famous hatsune miku songs. The band consisted of 11 or so members I believe, and Ryo was the only one actually designing and making music, the other band members were all in charge of illustrations, animation and the like for the songs. Only recently did they get an actual vocalist who changed her stage name to Nagi, and so they released 2 songs, Kimi no shiranai monogatari which was their debut and it was used as the ending theme to the amazing anime "Bakemonogatari". The group later released a new song called Love & Roll which was used for the anime Cencoroll's opening theme. Both songs were incredibly popular, Love & Roll in perticular scored number 1 on the Daily Orion Music Chart of Japan for 3 days in a roll*. Thus because of the band's popularity and Ryo's Black Rock Shooter, an anime of it is already in the making.
I still say that Hatsune Miku is the person in Black Rock Shooter, simply because I'm used to saying it, and I happened to learn about Miku first before black rock shooter.
Thanks to Kag for re-uploading the images for Miyuki.
*not sure about this but it's what I hear, it might be weekly, I'm not sure, all I know is that they are up there! xD
~PS: Go to my profile if you want to listen to the 2 songs since I have them playing on there, but my Gaia Online Profile not this one ;P Akuraia ~The Princess of Swords~