Writing as performance

Over at Snarkmarket, Robin Sloan makes some interesting points about writing as real-time performance. When I first read the title of his post, I envisioned a writer on stage, with a laptop, in front of a large audience of people observing the text he or she created on a large projection screen. Seems boring at first, but when you consider the potential collaborative contributions through Google Wave or another similar medium, how cool would it be if the audience themselves were adding text, editing storyline, or contributing in other unique ways? At the end of the "performance," every audience member would leave with a copy of the finished product. Or something like that. It definitely seems to be a possible reality, a step towards the mass audience text-production that Sloan hints at.

My question now is: how does this affect authorship? In my line of work, there is already enough scuffle over having seven or eight authors listed as contributors to a scientific manuscript. How could we even possibly start to evaulate the individual value of hundreds, maybe thousands of writers contributing to a text? These are exciting (and challenging) things to think about, especially if Google Wave delivers the potential it promises.