Hi all, I added a new ad unit in the top left of my site (as suggested in a message from Google) and it worked brilliantly - at first. In the weeks since, the CTR for that specific unit has steadily declined and is now about a third of what it was for the first few weeks. (It was added in mid-September, stayed at a high level until mid October and then dropped throughout late October and November). CPC has stayed roughly flat. Why do you think this is? I thought it may be banner blindness. Something new attracted attention for a few weeks, but then people began to ignore it. But around 80% of my visitors are new visitors, so it seems unlikely that ad blindness would be a big problem, doesn't it? Maybe it's the ads being served to the unit and I was lucky to get some appealing ads for a few weeks? Any thoughts greatly appreciated!