Casual vs. Hardcore Games

[Dan]

Just a few minutes ago, I was reading Satoru "Boss of Nintendo" Iwata's interview with Masahiro "Smash Bros." Sakurai over at wii.com, and came across an interesting quote:

Originally Posted by Satoru Iwata

Also, I think that fundamentally, we shouldn’t try and separate the casual gamers from the core gamers. After all, everyone starts off as a casual gamer. Some of these casual gamers will end up falling in love with gaming. Despite this fact though, I think that people too often treat them as entities that are inherently different [...] I think this is because we ignore the passage of time and tend to take a snapshot solely of the present when we talk about these things. But it’s different. People that love games and are really good at games were once, at some point in the past, casual gamers themselves. That’s why it’s so important to make sure that you continue to bring in new gamers. If you don’t, there will come a day when you don’t have any more customers.

What do you think? Is there a fundamental difference between "hardcore" and "casual" games? If so, what? Also, what about Iwata's assertion that hardcore gamers necessarily start off as casuals - is that true? Isn't it just as likely that a lot of gamers start off hardcore, and then gradually become more casual as they grow older and have less leisure time?

Now, I have my own opinions on all these questions, but I'm curious to see what you guys think. So: discuss!