Many people think of UDT as being a member of the "TDT branch of decision theories." And in fact, much of what is now discussed as "UDT" (e.g. in A model of UDT with a halting oracle) is not Wei Dai's first or second variant of UDT but instead a new variant of UDT sometimes called Ambient Decision Theory or ADT.
Previously: round 1, round 2, round 3
From the original thread:
Ask away!