User blog comment:Rainbowroad6w/An unreleased skateboarding Sonic game intended to be for XBox?/@comment-1535286-20110430032229/@comment-1535286-20110430033915

Couple things...

First: Voice recording is the first thing they do when they're making a game. Second: No game goes so far into beta that it looks that good without putting in the effort of voice acting. Third: Sonic 2 had new sounds ''and new sprites.