Just found this link ad on one of my blog this is for 728X15 ad unit for 5 links (I am using old code) What say guys?
Those kind of ads are showing when u have something wrong in ad code. Happened for me a few times. CSS is messing with google ads or something similar.
its not something new on the adsense side, tis something to do with your site coding which needs to be fixed
You better fix the code, or replace with a new one, before Google find it and terminate your account.
It's site scripts automatically modify your ads. it's not new format, also you against adsense TOS, you should change it detail:http://www.adulu.com/showthread.php?t=539