Does "Unbiased" have to mean you dont have an "Opinion"?

[Kantor]

Nobody is completely unbiased. Having an opinion, for example preferring the PS3 to the 360, introduces a bias.

For example, in a graphics comparison, you may be leaning slightly towards the PS3, but if the 360 wins, it wins. The trouble arises when the 360 version clearly looks better, and you say the PS3 version is better graphically.