It's basically "TV series," but distributed via the internet rather than over the airwaves, cable or via DVD. Netflix, hulu, Yahoo, Amazon and DirecTV have digital seires in the works.
I've dropped "TV" from my lexicon in describing this sort of series because it's going to become irrelevant if it already isn't. Cybergeddon
for instance is described as a "motion picture" released "as a series of installments to roll out sequentially" and has "social media and gaming" elements.
Rather than try to parse all that crap, I'm calling everything a "series" or "digital series" when it's necessary to distinguish it from cable or broadcast or movies or social media or games.