Very clever and calculated of the Parks Blog to include the Avatar blurb. Maybe they do know what they're doing.
That Avatarland is having problems is obvious, Iger didn't mention it during the shareholder meeting until he was specifically asked. If they wanted to draw interest in the project, then they would release some concept art.
As Cameron and Disney have different expectations of what Avatarland will be, it might be some time until a creative agreement is reached, if ever. Cameron will want the land to exactly replicate Pandora, which borders on being cost prohibitive. A reasonable compromise would be to start off with a single ride. Supposedly Cameron nixed a "Soarin' Over Pandora" type ride, and I can't blame him.
Joe Rohdes is a great imagineer, and obviously he is involved with seeing what can be salvage/created . . . but he wouldn't be at liberty to say the project is cancelled as it may survive in development hell for years without any real progress.
Does Disney want to snub Cameron by pulling the plug? Heck no, they'll tell him that they need to continue working together to find a compromise, even if they know in their heart of hearts that the project is dead. Why offend Cameron? He has a lot of muscle in Hollywood, and Disney might want to partner with him on a movie in the future.
Personally, I thin that while an Avatar ride might work, betting a whole land on the concept could fail. You need generic lands where rides can easily be replaced and retooled as needed. What do they do if fifteen years from now Avatar is history and people are tired of looking at a whole land decked out like Pandora? Adventureland, Frontierland, these are timeless themes, Pandora . . . not so much.