This. I don't really have the conscience to block the only source of revenue a webpage might have. But it's the Flash ads that make my otherwise silent 2009 Macbook Pro 17" (w/ SSD drive) roar like a 747 taking off, and that's where I draw the line. So I use FlashBlock and I'm fine. I think Google Ads (and in fact most ad providers) can detect this and display non-Flash ads instead.
Is there a way to disable flash but whitelist domains whose flash assets I will display? (Meaning I want to whitelist the domain actually serving the asset, not the page displaying them.) I suspect that approach would get rid of 90% of flash ads, while still allowing me to watch youtube or play the occasional flash game.
That's fine for now, but with Flash disappearing from mobile devices, and browser enhancements, we're going to see a move from using Flash to just using JavaScript for ADs.