Why do people keep saying that the iPhone App Store has an "advantage" over others because it has 100,000 applications?
Would it still have an advantage at 90,000? 50,000? How many does it really take?
A month or so ago, Apple wiped out all 1000 applications from a single vendor. Did anybody miss those applications? Probably not. So how many other thousands could be wiped out without taking a hit to its success?
Google stopped putting the "pages indexed" on its front page many years ago because it realized a key principle: the value is in the results, not the quantity.
The Android Market is definitely behind -- it is missing some nice applications. But not many! All the apps that I used to have on my iPhone are now available on my Android phone. Thus, Apple's App Store has zero "advantage" for me. How many other people are like me? Or conversely, how many people want and use all of those 100k applications?
I think the conversation should be rephrased into "do the apps exist, that a typical consumer wants?" rather than focusing on a mere count. That is the success of any app store.