This had slipped under the radar for me
https://www.reddit.com/r/backgammon/comments/1k8nlay/new_chapter_for_extreme_gammon/
After 25 years, it is time for us to pass the torch to someone else. Travis Kalanick, yes the Uber founder, has purchased Gammonsite and eXtreme Gammon and will take over our backgammon products (he has a message to the community below)
:(
Backgammon is "easier" than chess or go, but it has dice, so it not (yet) been completely solved like checkers. I think only the endgame ("bearing off") has been solved. The SOTA backgammon AI using NNs is better than expert humans but you can still beat it if you get lucky. XG is notable because if you ever watch high stakes backgammon on youtube, they will run XG side by side to show when human players make blunders. That's how I learned about it anyway.