Hi Dan: Steve and I debated this elusive unit of measure's true namesake. I, too, thought it was the WU factor--- with all credit (for first use I had seen) going to Herbie the Love Bug (of Sound Practices fame).
Steve insisted that the important criteria is "does it make you go woo (pause to catch breathe) woo, woo". Does it make you say "Woo--- that was cool." I thought this a bit more accessible as a qualitative indice than the moreso artsy-fartsy indici captured by the WU factor.
Upon further reflection, I sense that we need to capture both the visceral woo and the aesthetic wu dimensions in a new complex amalgam aptly named the Woo Wu Factor. Or we could call it the WWF and hope that the wrestlers don't take any special offense to our coining a term similar to their namesake.
The Woo Wu Factor can be shown with the appropiate X and Y co-ordinates graphically--- and then by drawing special Wu Woo loadlines one could further optimize a particular design for that special equilibrium point where the wu and woo naturally converge.
And that is how the Woo Wu Factor came to bee.
MSL
