OWN: Oprah Winfrey Network – a co-venture of Winfrey’s company and Silver Spring-based Discovery Communications – announced Wednesday that Oprah is expanding her role as chairman of the cable network to become its permanent CEO and its chief creative officer in the fall.

And, the current presidents of her Harpo Studios, Erik Logan and Sheri Salata, will become presidents of OWN, effective immediately. They will “work closely with” Discovery Communications’ COO Peter Ligouri, who found himself cast as in the role of OWN interim CEO back in May when the channel bounced then-CEO Christina Norman.

That was the latest in a string of exec departures at the network which had opened strong in the ratings in January – but, four months later, at times attracted fewer viewers than had the Discovery Health network it replaced.

Winfrey’s Harpo production company, which produced Oprah’s syndicated talk show, will now devote all its TV producing energies exclusively to fueling OWN, the companies said in Wednesday’s announcement.

Logan and Salata will oversee production for “Rosie,” a new daily talk show debuting October, “Oprah Presents: Master Class,” “In the Bedroom with Dr. Laura Berman,” and “Oprah’s Next Chapter” which will debut in January of ’12, among other programs.