GTPlanet have unearthed some footage of Polyphony Digital's Kazunori Yamauchi handling, what appears to be, a three-tiered Gran Turismo 5 retail package

The video focuses prominently on Yamauchi talking about the Mercedes-something-or-other (we don't know much about cars - Ed) and how it's likely to end up on Gran Turismo 5's packaging because it will "be the most exciting car at the time of Gran Turismo 5's release".

What's most interesting for us semi-petrol heads - who only care about cars because of Gran Turismo - is the way Yamauchi hands around what appears to be a retail package for Gran Turismo 5. That package includes three disc-cases. He does make it clear that packaging is not the final version, but never explains what those mysterious cases contain.

We're guessing a blu-ray documentary of Gran Turismo's making, but other suggestions include Top Gear episodes.

The full video is after the jump.