i built a plogue bidule patch before melodyne rolled out "dna" and it is extremely difficult to get the optimal fft parameters to get an accurate conversion. i cant imagine an algorithm that would get it right from analyzing the sample would be any less difficult. ableton's and cubase's options are pretty rough too. i am a drummer though, i am just trying to make up for my ears.
believe it or not, amount of local radio play still is the most referenced metric for booking consideration, at least on a profitable touring scale (as in touring for income rather than promotion). downloads and internet fanbase metrics have been used as well for quite some time now, just on a smaller scale, ultimately these decisions are up to the promoter, whether to trust facebook likes to turn into ticket sales, whether to trust a new artist being represented by a historically successful agent (this probably holds more value than any online clout), whether to trust the promoter's own instinct with their local market in deciding what acts will prove successful. ultimately, i agree that making a back-catalog free will benefit certain artists but probably not the domestically touring indie band.
With the rise of national corporate-owned radio stations, you have fewer program directors you need to convince to play your songs. But you're also competing with lots of other bands who sound just like you, because of the record company's tendency to sign clones of already top-selling bands.
Internet playlists (today's mix-tapes?) and college-radio probably have the greatest chance of becoming famous. Live venues work for local markets (Austin in particular), but breaking out onto the national stage is tough.
