That last ten percent is a tough nut to crack. Or at least it is for Gran Turismo 5 developer Polyphony Digital. Company head-honcho and GT franchise creator Kazunori Yamauchi says progress on the oft-delayed title is moving along a steady pace at around 90 percent complete.

“Gran Turismo 5 is about 90 percent finished,” Yamauchi-san revealed in a interview with Inside-Line. He added, “There are currently around 140 people working on the project.”

Jarringly enough, Yamauchi-san said progress was hovering around the 90 percentile mark during CES 2010 in January. Meanwhile, we’re still without a release date. Doesn’t exactly give a indicator of how close the game is to completion, making us question the practice of releasing such figures in the first place. Drums up hype, sure, but at the expense of disappointing fans.

Previously scheduled for a March debut in Japan, Sony moved the racer to TBD (to-be-determined) status in January. The company has remained mum on a release date ever since.

Kazunori Yamauchi: Gran Turismo 5 About 90% Finished, GT Academy Might Come to U.S. [Inside-Line]

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