As detailed by The New York Times, a growing number of publishers are using technologies that use CPU power, not humans, to produce content:
[Narrative Science's] software takes data, like that from sports statistics, company financial reports and housing starts and sales, and turns it into articles. For years, programmers have experimented with software that wrote such articles, typically for sports events, but these efforts had a formulaic, fill-in-the-blank style. They read as if a machine wrote them.
Currently, most of these articles are simple, if still impressive. They take data that may otherwise have to be deciphered by a human, and put it into a format that's easy to read, if not pleasurable to read.
While I'm sure we'll see more sophisticated attempts at letting computers produce content, right now, one might argue that today's computer-generated content is being used to do something useful: take interesting data and present it in human-readable articles. Nothing more, nothing less.
Content farming, of course, relies on human authors to write articles, often under the guise that those human authors have subject matter expertise, even though they frequently don't.
The end result: readers are lured in hoping to find information of a certain depth but they're often left disappointed because the articles are little more than search engine fodder.
Case in point: compare the Narrative Science-produced summary of a football game to the Demand Media-produced article about starting a business. If you were hoping to learn about the Wisconsin-U.N.L.V. football game, the former does a decent job. If you want to start a business, however, the latter is pretty lacking by any reasonable standard.
Which begs the question: is computer-generated content superior to content-farmed content? Looking at the above. there's a good argument that the answer is 'yes -- in some instances'.
While SEO is certainly a motivator behind both computer-generated content and content farming, taking raw data and turning it into informative, human-readable text will often be of value to a reader who would otherwise have to analyze the raw data herself, or read a similar article produced by a human.
On the other hand, content farmed content today is typically of much greater use to the publisher than the reader, suggesting that content farming in its current incarnation may have more limited longevity than might have been expected.