A small observation from the sponsored links today. Google appears to be testing a new, expandable ad format. Seen here with an advert for bed sheets at Littlewoods (I was searching for plastic sheets, the acrylic variety). Users have the option of expanding the ad to view some of the products on offer without clicking through to the Littlewoods website. Presumably, the cost is only incurred when a user clicks through to the website.
How Google`s auction dynamics affect your pay per click bidding strategies
Google’s auction for PPC adwords space is a fairly traditional second price auction - with a twist. How does that change the way you bid to pay the amount you really want to per click?