We propose "Web Engineering 2.0" to not focus anymore on how to engineer for the Web, but how to engineer the Web. Web Engineering has become one of the core disciplines for building Web-oriented applications. This paper proposes to reposition Web engineering to be more specific to what the Web is, by which we mean not only an interface technology, but an information system, into which Web-oriented applications have to be embedded. More traditional Web applications often are just user interfaces to data silos, whereas the last years have shown that well-designed Web-oriented applications can essentially start with no data, and derive all their value from being open and attracting users on a large scale. Such an approach to Web engineering not only leads to a more disciplined way of engineering the Web, it also allows computer science to better integrate the special properties of the Web, most importantly the loosely coupled nature of the Web, and the importance of the social...