I think we will still be interacting with games in the same fashion in 20-30 years personally.
A good question to ask is, do we want to interact with our games differently? I don't.
I love the way I interact with my games right now. The next best thing would be full on immersion. IE virtual reality. And that's a ways off.... I'd say its partially waiting on force fields to be created, that are not harmful to humans.
This way, a computer simulation, like the "holo deck" a lot of star war fans refer to... well all objects could be touched and interacted with. But it would require a very powerful computer to manipulate object texture... so that everything felt correct. Cause you don't want to bang that sexy short hair red head with the wonderful bust and it feel like sand paper now do you? hahaha... (And that's when bob decided to give up the early versions of virtual reality)
Games are still childish in story, well a lot are, so hopefully we will see that develop more.
Also, you know how the economy is slowing down right now? A lot of peoples hours getting cut, businesses closing down, well I live in the US... well I know that is bound to affect R&D cost and basically whether people feel like investing in anything new. Basically it slows down the whole process of innovation, whether in games, computers, science, etc... of course I would imagine it slows down others sectors more than others and vice versa...
Where I am going with this, is that it needs to be considered in that 20-30 time period. It eats up chunks of time.
