As a non-profit site, Vaxia falls neatly into the safe zone of American Fair Use legislation of images:

http://en.wikipedia.org/wiki/Fair_use

"In determining whether the use made of a work in any particular case is a fair use the factors to be considered shall include:

• the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes;
• the nature of the copyrighted work;
• the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and
• the effect of the use upon the potential market for or value of the copyrighted work."

In general, our character and account images fall well within these boundaries. To help guarantee that that continues to be the case:

• Images should be cropped where possible so that only a portion is used (say, the face on a portrait). The less of the total work is included, the safer we are in terms of Fair Use guidelines.
• Attribution (author name and link, whenever possible) should be given in the details for the picture, like before. That way we avoid impeding the ability of the artwork's creator to profit by it, if they see fit.

In other words, we can now use a wider range of art or photos on site without explicit author permission, though that's no reason not to give credit where it's due (see above).