Tired: making mashups with Acid. Wired: mashups built through machine learning.
It's only a matter of time until someone builds a system to build mashups automatically. First, a bot will crawl the web for popular music. Those samples will be fed into algorithms that compare beats per second, chord progressions, sonic profile and emotional tone, in order to score potential mashup matches. Each mashup candidate will then be fed through psychographically profiled sales data of its component songs to determine the optimal marketing impact of the mashup. Mashup "assignments" will then be fed to a distributed set of automated mashup makers, each programmatically tuned with different mashup style rulesets. Once the mashup is completed, it will be fed to an automated mashup distributor, which is responsible for seeding the file in various corners of the net, and tracking download and distribution activity. That data will then be used by to determine further marketing spend and potential "mass media" distribution strategies.
In the future, music won't be made. It will be grown.