Both sides have a valid point here. Technically, I would have to agree with Rick on this one. COM is king and it most likely always will be. This extension has been branded into everyone's head for more than a decade now and the other extensions will most likely make .COM only that much more desirable (at least here in the US). When you open your web browser and want a price on airfare would it be quicker to type in Southwest.com or Southwest.travel?
On the other hand, when we are talking about a time frame like 20 years it would be safe to assume allot of things will be different. Especially with how quickly technology moves! I don't think it's going to be these new extensions that will change the internet 20 years from now - It's going to be a gob of other things! As far as domain extensions go, .COM will still be at the top and many will lose money on all these new extensions (just what many big companies want)..But, technology and the internet in general will certainly be more different 20 years from now!