There's a lot of complaining going on now that Apple has unveiled their new iAd feature. I understand where these complaints are coming from (I don't care for ads either), but people seem to be blowing things out of proportion.
Anyone who thinks this means Apple is going to make you look at ads in order to use your device needs to step back and take a breath of fresh air. This will not happen. iAds will not show up in any of the core applications. As a matter of fact, I'm going to go out on a limb and say I don't think we'll see ANY Apple applications with iAds in them. One of the main reasons you create an ad-supported app is so people can try it out to see if it fits your needs, and if it's reliable. Apple's applications are reputable, and widely reviewed; they don't need to prove themselves to their customers the way third parties do.
There is no doubt that we will be seeing a lot more ad-supported applications popping up. I don't see this as a problem as long as Apple and the developers give us a way to disable the ads via an in-app purchase. Being able to try out a lot more applications before buying cannot be seen as anything but positive. If the ads bother you, pay up …if they don't, enjoy the free app. If you want quality apps to be both free and ad-less …go pound sand. The market will shun any apps that abuse the feature or aren't compelling enough to justify ad support to start with.
Ads are already used in apps, so it's nothing new for us end users. The good thing about Apple providing the service is that end users should start seeing some consistency in ad usage, quality, and etiquette. Oh, and it's yet another source of revenue for Apple—shareholders rejoice.
One final thing to note is that Steve said (during the Q&A session after the iPhone 4.0 announcement) Apple has no plans to stop apps from using competing ad services. Sounds like a win-win situation for the developers, and whatever makes the developers happy makes me happy.