Personally, I'm pretty sure that the "white" one is, in fact, sun fading, as looking at it closely, you can see that the words aren't all the same color "THE" and "ITALIAN" are the same color of white, but "JOB" almost has some sort of pinkish hue to it. Looking at the two side by side, the white on the text of the "variant"is clearly less white than the normal one next to it, again leading me to firmly believe that it's just some serious sun fading on the spine.
Edit: Looking at it again, I think there's even more evidence of sun fading looking at the two copies of Jak II that are to the far right. The one furthest to the right clearly has the red bleached out of the Jak II logo and the blue of the overall package is obviously lighter than the normal one right beside it. Seems a lot like a bunch of long unsold flea market fair mixed in with stuff that's been better kept.
darkchylde28's post in The Italian Job - Variant? (PS2, NTSC) was marked as the answer