I have added two new videos where you can see the popping of new detail.
It is very noticeable when the camera is close to a boundary and the new mesh comes right in front of it.
In these videos the clipmap loader is always trying to catch up with the moving view. In most cases it drags behind, as it really needs to load and process nearly 50 Megs worth of new meshes for each new scene. These meshes won't be used by the clients. Clients will receive very simplified meshes with all the detail projected. They will load a lot faster, but some of them will have to come from the network, so it is essentially the same problem.
Adding some degree of prediction should help. A prediction logic would load the clipmap scene for where the camera will be, at least a second ahead.
These videos are from some kind of weird terrain I was testing. I still need to go back and improve the terrain definition and materials. Right now it is a bit crazy.
If you look carefully you will notice both videos end in the same spot of terrain, but they start in very different places. Enjoy!