Apple has an impressive position in the music market. Through its iTunes store, the company currently has a 69% share of the U.S. digital music market and a 25% share of the total U.S. music market. Their position isn’t as strong however in the video market. This is especially apparent when you compare iTunes music and video sales on an average unit sold per user basis.

The iTunes store launched in early 2003 and by the end of the year it had almost 700,000 registered users. With the launches of the iPhone and iPod Touch, iTunes greatly expanded its customer base and they now reach over 100 million users.

The larger user base consequently led to accelerated musics sales. In early September total song sales reached 8.5 billion; they will probably surpass 10 billion in early 2010. (Update: Effectively, Apple reached the 10 billion songs sales point on February 25, 2010)

Looking at the average annual songs sold per registered user, iTunes initially had a very high amount- over 60 songs per user during its first year. This makes sense given that most of iTunes’ initial customers were early adopters of iPods and iTunes and probably hard-core music fans. After 2003 average song sales dropped off, but steadily grew back through 2007, until the user base ballooned (with the introduction of the iPhone and iPod Touch), resulting in another drop in 2008. However, the average has recovered between January and September 2009. Perhaps the latest wave of iTunes customers are becoming music customers.

As I mentioned beforem within video the picture hasn’t been as pretty. Total video units sold has been a fraction of average songs sold per customer. I thought that video sales would’ve picked up once more video-capable Apple devices were in the market (iPhone, iTouch, etc.) but that hasn’t been the case. Average sales per user dropped off in 2008, again, due to the increased user base, but video sales have not recovered like music. Rather there have been two sequential declines in average video units sold per user.

So is there a possibility that Apple will rectify its video position? Since April I have been speculating on the highly rumored iTablet. I believe that the device will be a multimedia marvel, revolutionizing gaming, digital magazines and digital video in particular, much as how the iPod affected the digital music industry. What was missing from my initial analysis was how Apple would need to couple its device launch with an evolution of iTunes, in terms of its video business model.

While iTunes does offer unparalleled access to content from many producers, it is easy to understand how many consumers might be stifled by its pay-to-own business model. An 45 minute standard-definition television episode on iTunes takes up about 450 MB of storage space. That is about 50 times more than a song. A song costs only half as much as the TV episode ($0.99 to $1.99). Therefore the real prohibitive cost to consumers from buying video content is disk space and not the purchasing price.

The logical solution for iTunes would be to implement a video subscription model. This week such a service was reported on at AllThingsDigital and Disney is rumored as being one the service’s early partners. Such an option combined with the “iTablet” would give Apple a much stronger customer offering for video, and would probably propel the company’s position within the market during the next few years.