Paul Kafasis has some good questions around how the iPhone App Store will work. I found the last one interesting though:

What about other pricing concerns?
Currently, we have a coupon system in our store, we can offer upgrade pricing for users who’ve purchased old versions, we can offer volume discounts for large purchases, and much, much more. All of these things, and more, help our bottom line. We’ll want to do them with iPhone Apps, but will we be able to? and the final comment:

The initial App Store launch is certain to have rough edges, as Apple just doesn’t have any experience in being a software publisher for other developers. Apple may not have experience being a publisher for developers, but it has a lot of experience being a publisher and it’s heard these kinds of questions, very loudly and very forcefully before.

I believe the answer was 99 cents.