Lame_Wolf - 11:34 am on Sep 30, 2012 (gmt 0)

a bright solid color to catch attention.

So, we are not allowed to bring attention to the adverts, but Google can.

They bring un-needed attention to the adverts. In turn, people will click on the arrow and then click back because they didn't think it was part of the advert.

Plus, there is nothing stopping people making a similar arrow for their "click here for more info" and pepper then around the site in the hope that people will click on the Adsense arrow, thinking it was part of the actual site.

They do not look too bad on 300x250, but it is huge on a 336x280 with a single advert.