lgn1 you make some good points.
I don't understand why the FTC would care about the user clicking on a paid ad versus an organic result since the user is not being charged - only the advertiser is. The advertisers probably don't want the the bright yellow "ad" logo because I am guessing that that will mean a lower CTR rate on paid ads.
But why are you so interested in Google keeping the white on white (very little differentiation between paid and organic)? Either you manage paid search campaigns and your earnings might drop as a result of paid clicks falling or you have a product/service and you advertise via Adwords and are concerned your number of clicks will drop. Which one is it?