I think this is a fantastic idea, and it's one I've long wanted to implement in our Guardians campaign.

I've done it a bit, doing complete write-ups (with images, just like you describe) for a major villainous organization called the Alliance (when the PCs figured out they were the main adversary in the world, taking territory away even from Intercrime).

I also started up something similar, but with a bit smaller scale, when I decided to keep updated records on all of our villains on 3x5 cards.  I realized one day (as GMs continued to add more and more villains) that we had over 300 of them to draw on.  Rather than using some old villain that had menaced the group before, people's tendency was to make somebody new.  That's fine occasionally, but I would like to see more of the rich, textured layers of something like the X-Men, where you have recurring bad guys (from Magneto to the Sentinels) or a rouge's gallery like Batman, with opposition that you develop a history with.

So I put down most of the basics of what you mentioned: Name; Identity (if publically known); Height; Weight; Known superpowers; Whether they were incarcerated or not, if they have a Criminal Record or not, if they are currently Wanted; Country of Origin, and then I threw a small image (a color photocopy of their 1" marker) on there as well.  I also included a few other personal details (any groups or affiliations they had in the campaign, and what "issue numbers" of our "comics" they have appeared in).

Cool idea, polarboy!  I think such a thing can add a lot to any campaign!