Welcome to WebmasterWorld Guest from 220.127.116.11
I have now made my ads look a bit gawdy, red and green, though on white background and I seem to have better click through rates.
I also moved some adds to the middle of an editorial - they don't have a border, but are quite standard, and the ctr was helped a lot!
I still havn't solidified my thinking about all this, but would like to hear other web worlders.
First, welcome to WW.
Ad format and placement can make a huge diffeece in performance. Ads that blend in with the page have not performed well for me. So, like you, I have made them stand out a bit. I use rotating background colors for my ads and that seems to help a bit. I think that helps because many of my visitors look at many pages during a single visit.
There is a lot of common opinion that placing the ads "above the fold" increases performance. I haven't found that to be consistently accurate either.
In the end, general rules about this are just that, general.
Webmasters need to keep experimenting untill they find what works on their specific sites.