YouTube has announced some changes to their Android app for mobile devices, making music video content available and also enabling pre-roll ads for partner videos.  But the most astounding thing in their entire article is this statistic:  YouTube is now serving over 200 million video views per day to mobile devices.  Consider this:  in 2010, there were 45 million smart phone users in the U.S., and 235 mobile phone users total (smart phones combined with traditional cell phones).  Now go back and look at the video views number.  It averages out to roughly 4 video views per day per smartphone user.

Music video fans should be happy to hear that the YouTube Android app now serves content from Vevo, the music video site YouTube powers in partnership with the record labels. And believe me, even if that news doesn’t move your needle, it’s big.  Music videos account for so many video views that most surveys, studies, and reports about online video leave out music videos altogether for fear of it resulting in skewed numbers.

The music videos that are coming to YouTube Mobile will also be coming with a few bells and whistles.  YouTube is adding some new features like artist bios you can read while the video plays, a musical note icon to denote that a video is a music video, a related artists tab, and a tab to help you discover more music from the same artist you’re currently watching.

Partner channels are surely excited about this update to the mobile app, because it allows their videos to show pre-roll ads.  That means more reach for advertisers and more revenue for videos running ads. YouTube says it’s the single largest step in mobile monetization to date.  Yes, people, the mobile ad market is going to be every bit as huge as they’ve been telling you.  How big? YouTube thinks it’ll hit $1 Billion in 2011.

It’s important to note that these updates are only for the 2.0 version of the YouTube Android app–which means you’ll need to be running Android 2.2 (Froyo) or higher to take advantage of them.

I’m pretty happy–though no longer surprised–to see YouTube making improvements and enhancements to their mobile app.  The advertising options for partners is the really big news, if you ask me, and it’s driven by the “200 million mobile views per day” statistic, I’m sure.  If mobile viewership continues to rise, which it will, then the ceiling on the mobile ad marketplace is still a long, long, long way off.