It would be really cool if you could assign tags to images like in adobe photoshop album. If users could assign pre-defined tags for common stuff like mech, angels, samurai, catgirls, ecchi, etc. it would make it easier to find images across series. Since one image can have any number of tags it would allow for great flexibility in displaying groups of images.
If a system like this were in place and I wanted to find a samurai wallpaper, I would only have to filter / search for that tag rather than look through all the anime categories that have samuri pictures in them. Such a system would require lots of time to tag images, but given the member base, it would be possible and any level of tagging would be preferable to none.
