At first, we are planning to invite about ten people to kick off a private beta\. We'll continue to steadily grow from there, but the growth will be limited by how well we think the platform can maintain usability and content quality\. Until we can support a wide array of users, Arbital will not be a suitable replacement for Less Wrong\. However, if everything goes well, my best guess is that at some point LW will be deprecated and Arbital will become the official replacement\. 6
Something more humble will probably work better, "hope" is a good word here. Deprecated -> archived ? And we'd probably want to bulk-import including comments before stepping up as official replacement ("good content" is questionable PR), the work will be in hooking up the sequences and similar to Arbital's nav features.