I’ve started reading Eliezer Yudkowsky’s 120 page document Timeless Decision Theory. Hopefully I’ll have something intelligent to say about it in the near future. If you want a taste of it but don’t have time for the whole think, I recommend Luke’s Decision Theory FAQ, as well as Eliezer’s post Newcomb’s Problem and Regret of Rationality to get a sense of the motivations for TDT.
When I started reading about TDT, I was initially skeptical that Eliezer would be able to escape the kinds of problems that plague these sorts of philosophical discussions. Just appealing to a couple thought experiments (in this case, Newcomblike problems) rarely settles anything.
But as I read on, it looks like Eliezer has some interesting things to say about precommitment, and may have a good case for TDT as a superior alternative to traditional precommitment strategies. We’ll see how my perspective changes once I’ve read the whole thing.