Did Congressman Anthony Weiner really tweet a photo of his, well, wiener? It's possible, but he also might have been "hacked" via an image service vulnerability that makes it easy for anybody to send a photo to a user's account.
The incident happened over Memorial Day weekend: Weiner's official Twitter account sent a link to a photo on ImageShack's yFrog service of a man's bulging underpants. Weiner immediately denied sending the photo, claiming that his account was hacked. As this is a common defense used by politicians and celebrities against Twitter and Facebook boo-boos, many Weiner-watchers took the hacking claim with a grain of salt.