Yes it is true, in case you didn't know Lucasfilm has altered the final version of the film(s) again. The Blu-ray releases include dialogue and visual effects changes. Here is an up-to-date list of the known changes. Click the links for the videos on YouTube.
Below is Mike's initial report breaking the news earlier in the week.
At this point I think its safe to say that we're all aware that Yoda has gotten a digital makeover in The Phantom Menace for the Star Wars Blu-ray releases. And while we knew that lightsaber effects have been updated and that some of the sound design has been enhanced, io9.com reports on three other changes.
A New Hope - Ben Kenobi's Krayt Dragon call has been changed.
Return of the Jedi - The Ewoks get eyes that blink. - Darth Vader yells "Noooo" as Luke is being electrocuted with Force lightning by the Emperor.
While io9.com and their source at Badassdigest.com are leaning on the side of these changes being real, we still have to classify this as a rumor until confirmed. We'll let you know when we hear back from LFL. And if we don't get a confirmation, you only have a couple weeks left to wait and see for yourself.
Click here for the full article at io9.com, which features some audio and video clips. The source article also includes a breakdown of how the rumors came about with links to our very own Jedi Council Forums. Make sure to visit the forums to weigh in on the authenticity of the change rumors.
UPDATE: Lucasfilm has confirmed to the New York Times' Dave Itzkoff that the Vader "No" change will be included in the Blu-ray releases.
UPDATE #2: Bryan Young from BigShinyRobot! got this from a contact at Lucasfilm:
"Yes, the updates are confirmed. We hope fans will wait to see for themselves how they fit into the Saga before making any judgments."
This builds on the report from the Times by further confirming that the other changes (the Krayt dragon call, the Ewoks, etc.) are also true.
UPDATE #3: Fan reaction has been from one end of the spectrum to the other. Here are a few "fan edits" showcasing their displeasure. ( They're pretty funny! )