Not snarky at all, there are lots of ways you might choose to measure information goods. One would be to apply a loaded cost model to a product and then figure out gross margins on units. You can could equate product releases to inventory 'turns' and then craft a valuation factor which develops some sort of freshness metric. These all toy with the question of whether the user population is an independent or dependent variable in the valuation. If the user population is strongly influenced the rate of new game introduction for example, you would discount a decline of current users against the value created by the new titles. So in that case freshness would be the valuation metric not user population. Or you could say the population of casual game users is fixed, and the only ones who would consider a new Zynga game already have a relationship with the company (independent value). So if people stop playing Zynga games then have they stopped being casual gamers ?
I think there is a lot of new territory here that is just being explored now.
Not to sound snarky, but was there ever another way?