AdSense allows custom styling and various other tidbits for premium publishers who get enormous amount of traffic every month. Most large portals are premium publishers and get such advantages.

Custom Ad unit as seen on Digital Inspiration
However, I recently noticed custom ads on Digital Inspiration, written by Amit Aggarwal, a popular problogger from India. His blogs (on WordPress and previously on Blogspot) receives ~2 million hits per month, and sports custom AdSense units. What caught my fancy was that the traffic levels to his blog are not large enough for a premium account.
Upon further searching and poking around, I found out the answer from the blogger himself, who said:
They have upgraded my AdSense account for serving Javascript based ads where you get some more control over the formatting of ads.
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I do not have much experience with AdSense, but Digital Inspiration is probably the smallest blog that I have seen such custom ads on. Have you seen such ads on small blogs (small when compared to other premium publishers)? Of course, custom ads on portals is nothing new, but I’m curious to see blogs with such ads.
Update: Amit Aggarwal (author of Digital Inspiration) informs me that it is indeed a premium AdSense account. Apparently, I miscalculated DI’s traffic, which is well over 2 million hits per month now.
Related reading
- How to get AdSense for Analytics for your account quickly
- Is Google experimenting with font options in AdSense?
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