Some talk about the Web 4.0 as a mobile web, the iPhone is a example. But I think that is the Web 5.0; the Web 4.0 is nearer than they think. The Web 4.0 is a Web 2.0 extension. The service developed to create the Web 2.0, now, they will be used to earn money by users.
The first steps on this way are LastFm (http://blog.last.fm/2008/07/09/calling-all-musicians) or the Getty Collection on Flickr (http://blog.flickr.net/en/2008/07/08/the-flickr-collection-on-getty-images/).
What do you think?