I dislike ads. For something useful, I'd pay for an ad-free version.

That said, I've NEVER clicked on an admob ad (andI I've had an iPhone since they came out).

I've clicked on SEVERAL iAds, and found most of them engaging enough that I stayed in longer than the initial screen. My expectations for ad content have been raised, and the combination of unobtrusive and rich works for me.

Then again, I run Click2Flash on my Mac, so I don't see most Flash-based ads, either. I don't run ....... because I know the impression count helps fund sites (like this), but I've thought about it.