No, he's not talking about web fiction per se, but yes, at the bottom of the article he does advocate electronic self-publication--particularly of serials--to get around the problems midlist authors are facing these days. So the piece is certainly relevant here.
Stackpole may be right about humans understanding stories "in terms of series and serial content." He cites television and the movies, others may cite Dickens; I would point out that even "regular" novels are broken up into episodes (chapters). Some people do find serially-published adventures exciting, but others prefer to read their episodes one after the other. Serials seem to be gaining in popularity but I personally don't see them taking over . . . at least, not yet.
By the way, this part, for me, is seriously scary:
4) Authors will be pushed to write faster, so the books can come out more quickly.
Bad news for me as a writer--I'm notoriously slow--and bad news for me as a reader, as I prefer my novels carefully-crafted and well-written. The idea that six to nine months (his figure) should be long enough to write an entire book, or that making such a demand could be considered acceptable business practice, makes me want to hide under the blankets . . . with a flashlight and an armload of classics.