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There's no such thing as an "unobtrusive ad." It doesn't exist. To those who justify ads in free apps or in websites providing free content, those web "developers" (there's a joke of a term if ever there were one) and app developers grossly overestimate their non-talents. If a free product can't cut it without the ads, it's probably crap to begin with. If it's free, then make it free. Otherwise, charge something for it.
 
I can see 10 potential objections to this:

1. The fear that ads served by Apple will provide a worse user experience than the ads already served by other services (seems extremely unlikely to me; ads already include everything from video to interactivity, and ideally you don’t get any of that unless you choose to tap--but with or without Apple, that’s always been up to the developer; do we really think Apple’s going to force unto us some whole new type of ad that’s more obnoxious than the status quo?)

2. The fear that ads served by Apple will be a real pain for developers to deploy, compared to other services (again extremely unlikely)

3. The fear that these ads won’t take the place other services, they’ll be in addition, so we see more ads than ever before: Apple-served ads alongside other services’ ads (again extremely unlikely: if a developer wants 2 ads they’ll show 2 ads—one more ad services won’t help them do that)

4. The fear that Apple will force developers to stop using other ad services they’ve already contracted with and designed their apps to use (again extremely unlikely)

5. The fear that Apple will include ads with the built-in apps, so you pay a fair price for hardware and then are also forced to watch ads (absurd)

6. The belief that more options for developers is a bad thing (but the option to show ads has always existed, with or without Quattro or Apple, and the option to sell paid apps is not going away—so buyers can keep voting with their wallets, and some people will always prefer free while others prefer paid)

7. The belief that Apple will allow ads in paid apps—like cable TV (maybe, maybe not—it could make sense in some cases where an app requires expensive servers forever—but developers won’t have to USE that option and few will: because that has ALWAYS been allowed, and users have always been free to take it or leave it—or give bad reviews)

8. The belief that free content should not exist at all, not even as an option for those who want it (but I for one do!)

9. The belief that good, quality free content doesn’t cost anything to create, and therefore should never have ads (but in fact it does cost something)

10. The fear that Apple might succeed in this business, and harm other ad companies that deserve more of that money themselves (I can’t see myself caring)

At least some people have sense.
 
This is what the Google and Flash war is all about, btw. A friend of mine who knows the business very well broke it down for me. It's all about mobile ads, Flash as the most common vector, and Jobs not wanting Google to make massive profits via the iPhone and iPad. I didn't really believe it until I saw this news. Now I'm totally convinced he's right.
 
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