The author: operator does seem to be working now. Can't say about the feeds.
Google takes a while when they add these features, and it's probably harder than it looks to implement them.
Author search is one of several features I'd requested when I spoke to several extremely nice and enthusiastic members of the Google search results team a couple of years ago (at the Google Dance in Mountain View), clearly very dedicated folks.
In both Books and News, I'd felt, Google was weak in returning authors' names. In Books, it was also weak in returning quotes, particular famous quotes that might also be frequently used in titles (eg, "to be or not to be", to cite a very well known quotation).
In News, journalist names didn't show up unless they were mentioned within stories.
They agreed, and told me that if such search features were implemented, it was because of that discussion. Who knows whether that was the butterfly landing that did it? ;)
I should mention that in Books, Google is now handling author search with a refinement up at the top... Books by William Shakespeare... or else... Books that mention William Shakespeare. It seems to work for most authors I've tried, even very obscure ones. The operator (not the same as the News operator) is inauthor: with the author's name in quotes, as...
If you use the author's name directly with the operator, it helps to put it in quotes.
Nothing yet in Books for short and exact but common quotations.