Advertising is expected to increase 20% to $31 billion in 2011, according to eMarketer. But online video is expected to grow more than twice as fast, or 52%. Given the fast-growing segment, the questions for both marketers, publishers and content producers - all three constituents that benefit from video advertising - which ad units are most effective and when can Web publishers see more consistent campaigns with CPMs (cost per thousands) above a single-digit price point? I talked to David Otten, founder and CEO of LongTail Video, a full-service video technology and advertising solutions company for that answer.

In this interview, David also talks about an influx of tier two advertisers/marketers that should increase the number of campaigns available paying out high single-digits to low double-digit CPMs to Web publishers who aren't super high-end content players, like Hulu.