Yeah it's Hatsune Miku. She's a virtual popstar who peforms live in concerts and has her own game series. Essentially she's a voice for a software called Vocaloid. You type notes and words into the program and you can make Miku sing anything, whether it be covers or original songs. You know the nyan cat song? That was originally sung by Miku. The famous verdion was sung by Momo Momone though.