Most people who are interested in web technology have no doubt heard about the long tail. Amongst other things, it describes common usage patterns of content or goods on the web.
I believe that by lowering the barriers to creation of simple applications, Pipes (and similar systems) will contribute to an abundance of available applications. The usage pattern of these creations will closely follow the long tail pattern. There will be a few major hits, but the bulk of the usage will consist of very niche applications that solve very specific problems.
Welcome to the long tail of applications.