“The under-20 age demographic…like to watch in discreet time segments.”

This certainly seems consistent with data showing that this age demo is watching less and less TV and spending more time on the internet, including sites like YouTube.  It would seem logical that this would be happening analogously on the mobile phone, that free mobile video sharing sites would be higher trafficked than paid mobile TV subscription services.  However, Quantcast is showing mobile YouTube (m.youtube.com) with less than 200k monthly unique visitors for July. 

Take into account the time mobile TV subscription services have been in market (a few years), compared with the age of mobile video sharing sites (most a year or less), and data packages and video enabled phones are now becoming mass market. I think it will be short order until third party sites that allow browsing and viewing of all media types (especially video) via WAP on a handset take off and overtake mobile TV monthly subscribers.  At the Mid-Year Review in LA, Greg Clayman (http://www.moconews.net/entry/419-audio-la-mid-year-digital-media-review) even made the comment that MTV is seeing “suprising” mobile video growth, with 4.5 million mobile streams “last month alone” (referring to probably June 2007).