I have no experience with them though... would love to hear from anyone who's used them. Did they convert? How are they compared to regular Google Adwords? Would you use them again? Do you recommend YouTube ads for a viral campaign?
Would appreciate any tips. Thanks!
Mid sized companies do 1. Retargeting 2. Demographic based ads(especially location based)
Big companies do branding.
Retargeting: If a user visits your website, you could ask google to add a tracking cookie to that visitor. You add additional information about that user like which stage of the funnel the user was in(eg., visited a product detail page, visited pricing page, went into checkout and dropped out, etc.). Based on this you could target a specific version of ad to that user, wherever he goes.
Most ads I see on Youtube are from companies that are in growth phase doing retargeting. Eg., Legalzoom, Zappos(and a few other e-com companies)
Demographic targeted ads: I saw that the set of ads I'm being shown have been changing drastically based on my location. And the ads I see also are different for me vs my friends who are slightly older. They mostly get insurance ads while I get beer ads.
To re-iterate, all this is empirical observation, and I don't have a first hand experience about this. But hope this helped