1. Xbox 360 & PlayStation 3: This version was released first and featured more polished graphics and a more complex physics engine, but also included a notorious "Werehog" gameplay section that many fans found frustrating.
2. Wii: This version was released alongside the console versions, but featured simplified graphics and gameplay due to the limitations of the Wii hardware. It also had a different "Werehog" gameplay section that was generally considered to be more enjoyable.
3. PC: Released later than the console versions, this version was a port of the Xbox 360/PlayStation 3 version, but with a few graphical and performance improvements. It retained the more complex "Werehog" gameplay section.
So, the reason there are "two" versions of *Sonic Unleashed* is that there were two separate releases for different platforms, each with its own unique features and design choices. The difference between the console and Wii versions is primarily due to hardware limitations and the desire to make the game more accessible to a wider audience.
Some fans prefer the Wii version's "Werehog" gameplay, while others prefer the more polished graphics and physics of the Xbox 360/PlayStation 3 version. Ultimately, which version is better is a matter of personal preference.