Internet TV platform Rokuannounced today that it has reached 15 million channel downloads from the more than one million people on its service. Roku’s growth has been spurred by its expanding selection of entertainment channels and the company’s recent move into U.S. retail stores.

Roku is simple and as a platform it is cheap. There are three options available ranging from $59.99 to $99.99 and consumers pay for the subscriptions they use through it, like Netflix or Hulu Plus. Roku now has 225 entertainment channels including paid and free services for music and video. The average Roku user downloads 15 channels.

The rise of Roku is a mixture of content, presence and economy. It was launched in 2008 as a way to stream Netflix to your television and has grown as live streaming sports (from the NHL, NBA and MLB) and movie networks (Crackle, Amazon Instant Video) have signed on. Moving into physical retail stores has increased brand awareness because, for good or bad, consumers trust that more than ordering from some amorphous Internet company with a weird sounding name. Other products tied to Internet and television, like SlingBox, have made successful transitions to retail stores as well.

Then there is economy. Early Internet TV adopters may be cutting the cord on cable television and rolling with Roku and what they can watch on their mobile devices. In terms of price, this has the potential to be significantly cheaper (depending on your preferences). Hulu Plus and Netflix are both $8 a month and most of the streams from major sports leagues are about $100 a season. Cable TV station bundles can be upwards of $80 to $100 a month, not including Internet.

We have contacted Roku for more granular information. What are the most downloaded channels (outside of Netflix, the original Roku channel)? Do users engage with all 15 (on average) channels they download or are three to four more heavily used? We will update here when (if) Roku gets back to us.

Update: Took Roku a little longer than we would have hoped. Here are some more granular numbers from them on usage.

Roku users spend 11 hours a week on the service. Of the 15 million channel downloads, the “vast majority of them are done manually.” Hence, not pre-loaded with the box. Of Roku users, 15% to 20% are cutting the cord on cable television.

The “big four” channels, as Roku calls them, are Netflix, Hulu Plus, Pandora and Amazon Instant Video. We could not get them to tell us the hourly usage of people on the service for these channels. The rest of the top ten channels on Roku are: Crackle, Newscaster (their in house news app), Revision 3, CNET, Weather Underground and MLB.TV.