It looks like Google are testing on a wider level the features I noticed back in October on one of their test bed sites.
1871 Media has noticed ads that allow readers of your blog to change the ads viewed to ones of a new topic.
It’s surprising on some levels that such an approach would ever work – as a web user I’m not sure I’d ever as a site to show me different ads – but obviously they’ve found this approach to be somewhat successful because they’ve been testing it for 8 months now!
I guess this shows that contextual text ads are becoming a more accepted part of the web and that some users are actually proactively using them to find the information that they seek.
In some ways this new feature is an extension of their ‘adlinks’ format which also gives readers an opportunity to choose to see a page full of ads on a topic. I’ve been using this format on most of my blogs for a few months now and have found it to be quite effective on some of my sites – largely depending upon where they are positioned and the topic of the blog.