Though it's possible we'll be writing the exact opposite of this five months or so from now, it seems unlikely we will see any announcements from Joss Whedon that he's bailing on TV and movies to make Internet videos anytime soon. There might be a lot of hedging about how he wished he had more time to do it, but... Unless and until the economics of Internet video change, television and movies are much more financially lucrative for Whedon than his Emmy nominated Dr. Horrible's Sing Along Blog that Whedon created with his brothers Zack and Jed and Jed's wife, Maurissa Tancharoen..
It seems Whedon can separate the world of fantasy and fiction that he explores on film and television from the reality that direct deposits into his back account.
Sci Fi Wire (which amazingly, and thankfully was not rebranded as the Sy Fy Wire -- they merely tacked on "Powered by SyFy") has a funny interview with Whedon on Dr. Horrible's Emmy nomination. Not for the first time, Whedon very overtly says there's not as much money in Emmy nominated Internet video as non Emmy nominated television.
You were sort of evolving into this after Dr. Horrible's success, but now that you are the Emmy-nominated co-creator of Dr. Horrible, you are the new guru and visionary for Web-based original entertainment.
Whedon: [With faux grandiosity] I truly am. And I have come to lead my people into the waters of unlimited creativity and wildly limited profit.
[...]Whedon: I'm looking for more people to do it. I'd be doing it more, but Fox forgot to cancel my show.
Whedon: Very awkward. They looked and said, "Oh, this is our bad. We forgot to cancel your show. You're going to have to make more."