What will the next generation of gamers be playing?

Here's a question.  What will today's young gamers be playing in ten years time?

To set the context to this question, there's 75 million Wiis out there, 135 million DSs, 45 million iPod Touches and 75 million iPhones.  Roughly 25% of Nintendo's userbase is aged under 18; on the Apple front,  a survey from 2009 indicates that 46% of iPod Touches are owned by people in the same age range, compared to just 6% of iPhones.

Bash these numbers together and you get the following:

There's certainly going to be a lot of overlap between these these demographics, but however you want to cut it, a significant portion of children have access to platforms with significant libraries of casual games[*].  So: what's going to happen when these children grow up?  Are they going to move onto to games which offer more complex, involved gameplay?  Or will they stick with casual, quick-win games?

Personally, I suspect the majority are going to stick with low-priced, quick-win games where they can receive positive feedback with little effort - and this scenario carries an additional risk: that games will become so devalued that their entertainment and financial value will collapse outright, triggering an exodus of gamers to other forms of media.

It can be argued that there are parallels with the golden age of arcade gaming - after all, those were the days when games were designed on the principle of "easy to play, hard to master", in order to keep playtime short while encouraging players to insert another quarter and try again.  However, there's several differences: aside from the limited availability of games (both in terms of time-on-shelf and regional releases), the games industry as a whole evolved away from these principles, as development houses competed with each other to add new features and take advantage of new hardware.  Now, games continue to be available for longer and game development has diversified, with many software houses focusing on existing gameplay principles rather than trying to explore new concepts - Bejewelled and Angry Birds are two prime examples.

Also, there's some evidence on the Wii that casual gamers are not migrating "up" to hardcore[**] games.  The bestselling list on Wikipedia contains very few games which could be considered hardcore - for instance, The Legend of Zelda comes in at #14 - below Link's Crossbow Training at #13!  And aside from Zelda (4.6 million), virtually all the other hardcore titles come in significantly below the 2 million mark, implying there's a relatively small "hardcore" demographic amid a mass of casual-only gamers.

Worse, companies such as EA are seeing significant revenue drops on the Wii.  Are casual gamers already starting to bow out?

[*] For the purposes of this debate, casual games are those which feature small chunks of self-contained gameplay and offer the player rewards for even a limited display of skill.  Angry Birds, Wii Sports, Bejewelled, Brain Age - and games such as Mario Kart, with it's features such as boosting the speed of slower players...

[**] Similarly, hardcore games are those which involve continuity (i.e. activity at point A impacts activity at point B), require some degree of player commitment (e.g. long playing times) and need practice and skill to progress.  E.g. The Legend of Zelda, Halo 3, Gran Turismo 5, etc...