I think it's always been about markets, for the most part. You can't sell a piece on car repair to Cat Fancy, at least not unless you have one hell of an angle. The exceptions to this rule are people who command an audience on the basis of name power, but even then, there are limits.

Publishing is undergoing a big change right now. On the one hand, the big companies are trying, as you note, to concentrate on "instant successes." A lot of other people are trying to sift through the rest of what's out there and pick up the nuggets for a pittance, or at least under terms that are very favorable to them in the long run.

Cheers...