Thomas Denton of comic blog Say It Backwards has a nephew who was diagnosed with cancer. A charity called Candlelighters helped his family out. Thomas decided to use his connections in the comics world to organize some charitable auctions featuring original artwork by various artists to give something back to the organization. Apparently Time Warner (who own DC comics, who in turn own Superman, Batman and most of the cool superheroes who wear capes) objected to the selling of the pieces featuring their copyrighted and trademarked characters on eBay, specifically Superman from what I understand.
Using characters owned by the major comic book corporations is pretty common in charity auctions at comic book conventions. This is not to mention that if you go on eBay right now there are a lot of auctions for artwork featuring those same characters, none of which Time Warner seems to be going after.
Thomas has posted a statement apologising to everyone involved in the affair (artists, bidders), but it doesn't seem right that he's been left holding the bag for trying to something for sick kids. Some letters to Time Warner's PR department might make them think twice about sending out cease and desist orders so wantonly, and who knows, might even prompt them to kick some cash Candlelighters' way.