I first heard the term "scalable" from a very media savvy client, Austin Furst. Austin's career path started at Time-Life (pre Time Warner days) and he worked on all the successful new products - from People Magazine to HBO. He is also the founder of Vestron Video, one of the first 3rd party companies to distribute movies and other high value content on Video Tape. Vestron evolved into a production studio, its most famous film being "Dirty Dancing." To make a long story short, suffice it to say, that Austin learned a lot about the risks of investing in the "hope the lightening strikes" business model. My assignment was to help develop business ideas that were "scalable" - the capital required scales up with revenues, in other words: prove you can generate revenue profitably first.
However, as I have participated in countless meetings with venture firms and prospective strategic alliances in the media world I've come to understand that "scalable" has a second much more common meaning. Specifically, prove you can generate scale (a large audience) first and then figure out how to generate revenue from them.
I suspect, but I may be wrong, that Austin's definition of "scalable" - prove you can generate revenue profitably first - will become the new meaning of the "scalable" mantra.