The OPA study is effective and persuasive. But, I also think it should be taken with a grain of salt. To say that consumers prefer 30-second ads is inferring quite a bit. Most, if not all, viewers would prefer no ads. Wouldn't you like to watch "Lost" without commercial breaks? To me, the findings suggest that 30-second ads are far more effective at communicating a brand's message. It makes sense that getting 30 seconds -- rather than 15 -- of an engaged consumer's time will offer a better chance at communicating your value proposition. But, for better or worse, you have to factor the consumer's and the publisher's interests.

Consider the following when inserting 30-second pre-roll ads as opposed to 15-second ads (or other forms like in-player banners and user-initiated video ads):

• Did consumers end up watching fewer videos on the site? 
• Did their overall viewing time decrease? (This is important considering Nielsen's announcement that they are moving from page views to time spent on site).
• Did the site maintain the same visitor retention rates?
• How much revenue based on an effective CPM basis is the site generating with the different ad units considering 30-second slots are worth more to advertisers?

Overall, this study helps frame and advance the debate of 30-second versus 15-second ads. Stats like these are incredibly important, but I don't like generalizations such as "consumers hate pre-rolls." I'd rather see statistics backing up statements that express the interests of advertisers and publishers alike. As an exchange, SpotXchange has powerful opportunities to collect a range of performance stats and, as a result, we can advise both advertisers and publishers about best practices and emerging trends.

We have identified some interesting trends since our launch that relate to this very topic. When SpotXchange launched in the fall of 2006, the bulk of the ads we served were 30-second spots, and our publishers accepted that length since that's what advertisers had to offer at the time.

Today more than half of the ads we serve are 15-second spots. This does not imply that advertisers are accepting the 15-second spots as the de facto, because our experience has been that they still want that 30-second commercial. But they are submitting to the 15-second ads for a variety of reasons, including publisher requirements, industry debate, available video assets, et cetera.

For the most part, our publishers are okay with 30-second ads, but they continue to be vocal about wanting shorter ads of 5-7 seconds. This leaves the 15-second spot as a solid middle ground.

By and large, the OPA study provides more than just valuable data. It also works to create a common mindshare among those in a space that is still in its infancy.

I suspect media buyers, particularly traditional agencies, are struggling with the idea of expanding their traditional TV ad campaigns to the online world primarily because no standard metrics are in place to judge a campaign's success.

TV metrics leave a lot to be desired, but they are established and accepted by everyone in the industry. In contrast, online metrics are powerfully accurate, informative and provide an amazing positive feedback loop to judge a campaign's success. However, a set of industry-wide, commonly accepted metrics for the online video ad space are yet to fully mature. So it is important that the OPA and others continue to share their findings with the industry to help navigate those standards.