Yeah ... now this is possible and now you can change the font in your adsense unit. But there are only limited font style such as Arial, Times, and Verdana.

To apply this ... follow this step

= Go to My Account
= Click edit button of Ad Display Preference
= Now you will see Standard Adsense font family and select your choice.

I am going to use Verdana as this one is nice looking and working as well. What is your choice guys ?

thank you, I need to change fonts as well

thanks, what areyour other settings? like link text color, link color that are working well and convert better?

Verdana is good choice mainly because of it's readable. If also blend with your content font, just perfect.
It's good to point that you can change the font only if you have a Latin language site. For people like me that have and Cyrillic sites it a little bit stupid... but yeah Google.

I haven't tried yet changing the font type in adsense units.. I think this feature is really useful so that your ads will blend on your content...