In a move that has been highly anticipated by content creators, online publishers and advertising agencies, the Interactive Advertising Bureau (IAB), the industry trade organization of online publishers, will announce today that the standardization of online video advertising has been finalized.

Many of the standards, including specifics for companion ads and pre-roll ads have been widely accepted and implemented. 

But the newest form of video advertising, the overlay ads, has lacked standardization.  The new guidelines keep the videos short, as long as 15 seconds and as short as 5.  The IAB also allow "persistent" ads, meaning overlays that stay up as long as the clip is playing.

The maximum length for pre-roll is 30 seconds.

Most of the new standards being announced tomorrow have been posted to the IAB membership for comment.  You can find them here.  For an overview on the online video market and the importance of the new standards, check out this report from eMarketer published last week.

There is still more work to be done in the standardization of online video advertising including pricing the value of engagement. This point was driven home in my interview with Rebecca Paoletti who is director video sales strategy at Yahoo!

I visited the IAB offices in Manhattan on Thursday to chat with Randall "Randy" Rothenberg, president and CEO of the IAB.  Randy, a former New York Times advertising columnist and author, frames the opportunity and challenge in online video.  He says the power of the medium is defined by the "opt-in" engagement of the consumer.  For the ad agencies and publishers, the challenge is how to keep content relevant.

Below are examples of video ad units provided by YuMe, an ad network which serves several different ad units into video streams.  When you watch Beet.TV today, you will find an overlay ad inserted into our stream with YuMe technology.

— Andy Plesser