I was at Animal Kingdom tonight (Saturday). The park closure time was 10pm. I walked by the Tree of Life around 9:20pm, and I stayed there about 10-15 minutes. There hasn't been any of the vignettes, and there was no movement from the animal on the Tree. Very few people stayed in front of the Tree, compared to the crowd when the show goes on.
While it didn't rain on the park, there was a lot of lightnings. However, I suppose that the Tree of Life projection show isn't really weather sensitive. (Similarly, during the 8:45pm representation of Rivers of Light, the four floating animals barely appeared on the show; they exited from the backstage river at the appropriate moment, but immediately returned towards that river rather than joining the lotus.)
Finally, I thought that Tree of Life awake each night. However, on the park times guide, it was scheduled only on Friday and Saturday, this week. I suppose the 8:30pm closing time, the other nights, is too early...
Well, all that was a bit disappointing.