Google search result issue?

Hi just checking. From my knowledge....in the Google SERPS, one can tell the difference between adwords results and organic results because the adwords results would be in a diff background? For those who are wondering, I am not talking about the ad results on the right column but the ads in the middle, above the organic results. However, I noticed recently that there is no longer such difference so one cannot easily tell. Of course if I hover my cursor above the link I am able to tell from the link. But just want to check if this is indeed so or if its largely because of my browser? I am using firefox. Dammit if this is a true change....