Screenshot dump!

First, a couple more shots of the rail line, descending into the grove ahead of the Ubertree. I'm thinking of building the vegetation further up the second level of the structure. The first level just has a lot more atmosphere, being partially hidden.

If I hide the upper levels a bit more and increase the density of the surrounding foliage, this entry will feel a lot like stumbling on something, rather than arriving at a known location.

The lower level is a quiet library, with a private reading room, off to the side. There's an air of peace and seclusion, on account of the small windows and the foliage making it easier to see out than in.

The upper level is less dominated by the trees, as they provide structural support, more than anything else. The windows are also larger and less obstructed. Sleeping quarters and two sitting areas are located on this level, as well as access to the observatory.

Finally, the top level is the observatory. I put a small gallery in the center, partially to keep the room from just being an empty floor, and partially to keep people from accidentally tumbling down the stairs. My other observation tower is about the furthest object
Minecraft is willing to render at this location, so there's a good view of the rail line and three of the domes. It's nature in the other directions, save for a couple lines of torches, in the distance, left by one of the server's wanderers. The lit trail makes for a pretty cool effect, at night. You'll have to come out and visit to see that, though.

In other words, until were sure that 1.8.1 isn't going to make the server fall over, we are going to stick with 1.7.3 for the time being.
Thanks for the update! I can't say I'm disappointed by the delay. I'm not quite ready to test whether or not the Endermen are willing to build on my roof or able to teleport through glass.