They'll just be A/B tested from out of a collection of alternatives. (After all isn't that what the artistic filter is supposed act as a proxy for in the first place.)
Better yet they'll be copy tested on a quick little panel of a thousand people. PicFu on Mturk is about to get a crapload of business. Who needs to decide when you can have the hive decide for you, and it will be the best result out of he given options because you just asked a thousand people and you have all their metrics.
The colloquial usage of "automated" isn't literally "no humans are involved at all" but rather more along the lines of, the effort involved or expertise required is orders of magnitude lower than it was previously. I think for this case, it holds.
Maybe, maybe not. A different model could predict whether candidate images are or aren't a good fit and beyond that you could generate multiple options and A/B test them generating new permutations on the fly based on engagement metrics.
But how many humans will still be necessary, in comparison to the status quo? How much will this affect the "market value" of normal / non-famous illustrators?
But on the plus side, even small publications will get really pretty, custom illustrations! :)