Well, launching a web browser from an app is a lot less disruptive when you have multitasking.
This will be big because game makers will buy these by the boatload. I'll go on record right now predicting game ads will be over 80% of what you see on these.
If game makers take up this approach in force, that will be a fair sight better than the status quo of supporting "free" games by way of in-app purchases (that are essentially mandatory to get the full experience of the game).
I know some game makers, and I'm pretty sure none of them like the current paradigm much either. It's a pain in the ass. Because of the horrendous distribution system, to succeed on the iPhone you have to be constantly gaming the app store, and every hour you spend doing that is an hour you didn't spend making your game better.
This is why we've never touched it. On Facebook, we just have to make our users want to invite other users. We don't have to constantly release new versions and incentivize users to download them just to get ourselves back in the top 20. There are some tricks, of course, but they're less of a detour from the desired path, if that makes sense.
iAds will make success on the platform a numbers game. Every free app will run it because it can't pay worse than the current options, even with the 40% rake. Paid apps will break out the spreadsheet and almost certainly find a CPA below the app's price for a paid one. My totally off-the-cuff guess is that with a really engaging iAd you'll end up paying $1 to sell a $2 app, at which point it's all about volume. Selling a million like that might be doable, and now we're talking money in line with what Facebook apps can make.
Still, the problem will be that the most successful iPhone apps make about the same amount lifetime that the most successful Facebook apps make in a month. But the odds of succeeding may now be high enough to make it a worthwhile play.
The only issue might be privacy. Your phone book is full of people, 90+% of whom probably do not have an iPhone. On Facebook, every one of your Facebook contacts has clearly already divulged to you that they are on Facebook.
Still, I imagine if Apple made an opt-out method of automatically friending all of your email contacts who have iPhones (or at least an opt-out method of seeing them) it would be popular.
Seems to me like their "Game Center" thing might address this. I personally avoid Facebook, but if I look at my iPhone and can see that 3 of my friends are playing a particular game, I would be influenced much the way I imagine folks who receive Facebook game invites do.
Actually, I'd probably be influenced more, since I know some Facebook games force you to recommend it in order to get access. But if this game center, like XBox Live, can just show me what my friends are actually playing... that's the best endorsement they can give me :)
Mobile ads probably need 'bookmark for later' as a primary option, as in: I'm in the middle of something else right now, but that's interesting enough to review when I have time.
This will be big because game makers will buy these by the boatload. I'll go on record right now predicting game ads will be over 80% of what you see on these.