Robert Scoble is talking about how YouTube is going long-form and why it will be more profitable for them and more attractive to advertisers. His argument is that if someone is willing to sit through a 30-minute video online, then they are more engaged and will more likely be customers for advertisers:

Someone who’ll watch a 30-minute video is HIGHLY ENGAGED. They are far more likely to become a customer than someone who just watches a two-minute entertaining video.

Here’s why: long videos are a filter. Only the most passionate and most interested people online will watch such a video. Those who aren’t interested wouldn’t even consider watching a long video.

It’s a nice theory, but I don’t buy it. First, I believe that a large chunk of people that consume online video do so at work. That environment allows you to watch a 2-5 minute video and then get back to what you are doing. It also allows for more interruptions, while still being able to finish the video. How many times are you going to tolerate being interrupted at work by co-workers, phone calls, or email before you throw in the towel on a 30-minute video?

People just don’t watch long-form video on their computer. My own video work has fallen victim to this as well. I’ve done many videos that were 15 minutes long and after watching them with colleagues or with an objective eye, it was clear that people get antsy after 7 or 8 minutes. It made me cut deeper during the editing process and really get to the meat of the content. My productions are better for it.

Don’t get me wrong, I’m not saying that it is impossible for a long-form video to find an audience online. After all, Scoble does just fine with viewership of his pieces - although it doesn’t hurt to have his brand name and the weight of Fast Company behind him. Additionally, sites like Hulu that archive complete TV shows and movies will find an audience because they are serving up content that already has a traditional media audience of millions. It’s hard enough for unknown prosumer / UGC / pro content to find an audience with short, well-paced pieces. I believe that becomes an even bigger challenge when the content starts getting into the 30-minute range.

The other side effect I see of YouTube allowing video longer than 10 minutes is increased piracy. They can barely police their network efficiently now with a 10-minute limit. This opens up their network to people adding complete TV shows or movies. That means their copyright department is going to be working lots of overtime.

Advertisers want engagement. We know that. To me, that is better measured by how many people comment on a video or link to it, rather than making the assumption that committing to watching a longer video makes them a better potential customer.