I have seen these sort of reports quoted even in the past by multiple sources and they remained just as plain rumors and nothing happened. I only hope it remains the same this time as well. In 2012, few said that Panasonic is closing the plasma business in 2013, but we saw the revival of plasma this year with the kuro killer models and of course Samsung has caught Panasonic just like that.
Let me give my insight into how the process is prolly run from a business point of view (with little humor)
Shutdown is not an overnight decision hence "nothing" seems to have happened. This is what is happening inside Panny.
a. The company's sales slide qtr on qtr and year/year and hence its fixed costs increase. Also others are able to offer a cheaper/better model hence market share also decreases. Doubly whammy and at some point they declare a loss. (T - 3 years)
b. Share price tanks and angry shareholders call "Panny Chairman" San and hammer him. He asks for patience and promises that next year Panny Plasma will bounce back.
c. Meanwhile, Panny San calls Plasma San and hammers him. Orders a business review and his plan to get profitable. (T - 2 years)
d. Decline continues, shareholders get MAD. Panny San fires Plasma San and gives his replacement 2 years to make profit or get out. Also, Panny San quietly approaches a few bankers to reach out to White Knights (other firms, PE's who could buy Plasma div out). Panny makes a statement saying "We are firmly behind Plasma, blah blah. This is when the rumors start. (T - 1)
It would take anywhere from 1 - 4 years to find a buyer. My sense is that we are at a stage when Panny is desperately looking for a savior as it bleeds. The end might come this year or next, but they do look terminal.