alika - 12:21 pm on Oct 29, 2010 (gmt 0)
I got that email as well. They say that the more ads in the units, the higher the CTR.
# of ads / CTR increase
4 = 32%
5 = 41%
6 = 47%
7 = 52%
8 = 55%
9 = 56%
The principle is simple: the bigger the ad unit (the 7 or even the 9 can occupy a lot of space), the more visible it becomes and users are more likely to click on them.
My site got featured in this advertising network's site before because of the huge, huge jump in our income from using one of their bigger ad units at the bottom of the articles (not this new ad unit, but the one they launched last year). It may look garish (heck, it IS garish and big), but the jump in income -- and they way it holds up month after month -- is really something to consider.
There's a right placement for it, though, as these big ad units don't really go well at the top of the content. We've put ours at the bottom and it really works. We used to have an Adsense large rectangle at the bottom, but decided to put all our Adsense above the fold and give this space to this competitor. So we're definitely trying this big ad unit this competitor has announced and see how it goes.