That's true, but I think the beasts might know...due to being so close to The Rikudou...I think that's why Kurama wasn't speaking so secretly with Gaara. Just a thought.
OT: Yes I've said this....and I agree naturally. I believe that's why the moon was shown and the Tree is already reflecting on the moon. The fruit is there.....of course it's just speculation.
Wouldn't the Bijuu know of this though as well...since...you know...the tree is the Juubi and the Juubi is them? I mean the bijuu should know of this in my opinion. maybe the felt the fruit was about to blossom and they told this to Gaara should things turn sour as they have.