If you want to buy the the latest entry in the Super Mario Bros. franchise, you won’t have to leave your dorm room, house or other dwelling.

For the first time in its history, Nintendo is allowing owners of its 3DS console the ability to buy and download a full, retail game directly to their device. With this move, and plans to continue to make retail games available for purchase on their eShop service, Nintendo joins other console developers in offering digital download services for retail titles.

We’ve already seen a similar change take place in the music and book industry. Thanks to iTunes and your mobile device, if you want a song, you can get it with (almost) no questions asked.

The gaming industry, on the other hand, has had a much harder time building up a digital distribution model. Taking into account the differences between these media, it’s no surprise.

Now let’s be clear. We’re talking about full retail console games like Call of Duty and The Legend of Zelda; games that have a lot of content to justify a higher price tag. Not quick-buy smartphone games like Angry Birds or Cut the Rope.

There are a few major changes that come with this technology. First of all, there is size. Let’s remember that the internet wasn’t always as high-speed as it was today. One of the reasons iTunes worked was because the average music file weighs in at about 5 megabytes. Some of today’s games, on the other hand, can take up well over 5 gigabytes, 1,064 times more information than the average song. Try doing that over dial-up.

Then there’s the consumer expectation of tangibility. Most audio downloads set you back a measly $.99; barely enough to even think about. For the higher price that today’s TripleA games demand ($40-60), people like something physical to show for it. How would you feel if your computer or console where your downloaded game is stored were to break? What’s the guarantee that you’d be able to use it on your new device?

These are challenges that the gaming industry is facing as they continue this brave, new digital transition. Game companies have every incentive on their end to do away with physical retail buying altogether.

Think about it: direct downloads mean developers can sell more directly to the consumer and eliminate the middle men standing in their way.

However, going back to tangibility, consumers naturally expect a lower price for something they can’t actually hold.

A switch to digital means that game companies will have to change many of their own practices. A retail game and a downloadable game are two very different things. Lower prices as well as the power to transfer the game to whatever device you want it on are just some of the many things that will have to change to make downloading a justifiable option for consumers.