A person (mostly girls) who does an average of 3.1415926 quizzes per hour. This accounts for about 95% of Facebook/Myspace's internet traffic. Quizzes range from stupid to incredibly retarded and are known for being the best time killer. A typical quiz will start with "I was bored."
The species of "quiz whore" is yet to be further researched as social networking websites gain more popularity and become ever more technological. Scientists are internet geeks alike are speculating that the main goal of the "quiz whore" is to get attention.
There is also the "quiz whore disease" which makes anyone who reads the quiz unable to stop themselves from ctrl+paste'ing it to complete themselves.
The Quiz Whore is said to be extremely dangerous, if attacked by a tempting quiz, terminate with extreme prejudice.
You want an example?
Go on Myspace or Facebook, many quiz whores, nuff' said.