As a general rule of thumb, I avoid sports metaphors - partly for reasons of style (I think they're over-used and cliched) and partly for reasons of personal preference (I'm not much of a sports guy). But sometimes, a sports metaphor fits so well it would be silly to avoid it. So, here goes:
Being a writer is like being a baseball player.
Both are fun activities, which lots of people participate in. Some do it on a local level, just for fun, without any aspirations of making money at it. That's not a bad thing. Others move up to the various minor leagues, where they work hard, make sacrifices and are rewarded quite modestly (if at all). Also not a bad thing. And then there's the small number of people who make it to the Big Leagues. But the company softball team isn't going to pay the same as a spot with the Yankees.
Asking how writers will make a living in the digital era is a bit like asking how baseball players will make a living now that the games are broadcast on television. Those who disparage the eBook experience as inferior to the experience of holding actual paper in one's hand are just like those who (correctly) say that watching a game on TV is not the same as attending one in a stadium. It's still baseball - it's just a different kind of baseball. That's not bad (and the players manage to survive, don't they?).
It's not a perfect metaphor - big name writers don't get product endorsement deals, for exampl (we're not likely to see a commercial saying "Stephen King uses Bic Ballpoint Pens..."). But I think there's something there...