"It's you " - In 2006 the Time Magazine declared the Internet user the Time's Person of the Year. Considering that in March 2007 there were more than 1.1 billion people using the Internet, which is in fact a sixth of the world population, this election is not surprising. This should be reason enough to take the Internet user serious and to not underestimate his demands and expectations. However, even though there are numerous guidelines as to how to make a website successful, the provider and the user may have different perceptions of the website. Up to now substantial research has been...