I checked their karma before replying, so I could taylor my answer to them if they were new. They have 1350 karma though, so I asume they are already familiar with us.
Same likely goes for the existential risk segment of EA. These are the only such discussion forums I'm aware of, but neither is x-risk only.
If it's worth saying, but not worth its own post, then it goes here.
Notes for future OT posters:
1. Please add the 'open_thread' tag.
2. Check if there is an active Open Thread before posting a new one. (Immediately before; refresh the list-of-threads page before posting.)
3. Open Threads should start on Monday, and end on Sunday.
4. Unflag the two options "Notify me of new top level comments on this article" and "