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Now, instead of being stuck with the default font for all your AdSense ads, you can choose between three different font faces: Arial, Times and Verdana.
While the choice is not as funky as some publishers would want, it's still better than being stuck with "Standard AdSense font family," which is still the default. Beware, though: as Google warns on the official AdSense blog, the standard font has "performed well across browsers and displays." By changing the font, your results might get better, but they also might get worse.