Interstitials are a rich-media form of advertisement, that, in my opinion, is as close to TV commercials as web advertising has gotten.
Interstitials are not banners, they are not popups, they are full page ads that load between page views on your site. Most interstitials display for 10 seconds or so before forwarding the user onto the page they were trying to view, and almost all interstitials include a skip button if the user does not want to wait.
Some people I’m sure find these types of ads annoying, however I find them less annoying than popups, because they are at least contained in my original browser window. Also, I feel that much of the ire about popups came about as a result of multi-popups being used at once, or popups spawning additional popups when you try to close them. None of these things happen with interstitials.
Really though, the reason I love interstitials is that I see them as more or less the only ad format that can easily and reliably foil every ad blocker.
The concept of ad blocking is not without controversy, some people see it as their right, most publishers though see it as stealing. If you do not like the ads on a site, and you know that the site is ad supported, ethically you shouldn’t use the site if you have ad blocking installed. Popup blockers are understandable, I think, as they can be really annoying, can confuse less knowledgeable Internet users, and even slow down some PCs. However those blockers that block banners, I consider it stealing. Some people might claim that banners need to be blocked to stop drive-by-downloads. That is a weak excuse though when you consider the fact that switching to Firefox will stop them more easily, and also when you consider the fact that ads as benign as Google text ads get blocked by blocking software.
I don’t want to turn this post into a discussion on ad blocking, suffice it to say that I consider it a threat to the website publishing industry, and I consider interstitials to be an answer to that threat.
The reason is that interstitials load in the same browser window as your site, and they load on a different server from your site. If you know which pages on your site are to serve interstitials, you can detect, using the HTTP_REFERER variable, whether or not your visitors actually viewed the ad or not. If they did not, then you know they are blocking ads, and you can automatically forward them to a page explaining how your site is ad supported and how they need to turn their software off. You could accomplish this same thing with cookies. Getting around this type of setup would be difficult to impossible for ad blockers. They’d need to generate fake cookies or referrers and then you’d need to make just a minor change and it wouldn’t work until they managed to do an update.
I also like interstitials because I find them to be useful in monetizing a resource intensive section of your site, such as a search feature. Full text searches can be resource drains and so by say adding an interstitial in between the search and the results you will help offset the cost of providing the feature. Additionally you could even say something like “While we’re carrying out your search please view this ad from our sponsor.” I really do not think this would annoy many people.
Interstitials should in general be treated like popups, meaning you should only use one per user session, or at least never use them on consecutive page views.
The downsides to interstitials are that they are not as of yet widely available and they do not always pay well. For instance Fastclick one of the view networks to offer a separate adcode just for interstitials, pays around 30-40% less for interstitials than they do for popunders. Interclick a company that specializes in interstitials is a little better, however at this time I cannot recommend using them as there have been reports in the forums of them stiffing publishers on payments . My favorite network for interstitials so far is Tribal Fusion. They do not have a separate adcode for interstitials, and instead serve them in combination with the occasional banner ad, they also do not have much inventory. However, the rates are stellar. Its not uncommon for me to see interstitials at $10 CPM or more with them.
And on the topic of interstitials…
Google recently started beta testing rich media ad formats with their Adsense program. These formats include expanding banners, floating ads, and interstitials. I couldn’t be more excited about this. If the rates end up as good as I think they could be, then I might finally be able to drop using popups altogether.