Well tcm, now for another point of view:
Yes, Rubicon makes no mention to the events of Marathon: Infinity. Durandal is "Durandal" and not the Thoth-Durandal hybrid AI we knew when the trilogy concluded.
However, I still believe (since I'm creating a scenario "Where Monsters are in Dream") that the Rubicon universe is still the Infinity one.
Certian events transpire (around a Rogue star mentioned in a Rubicon terminal) which separate Thoth from Durandal. Just look to Durandals highly composited Rubicon logon for some clues there.
What about the Infinity end screen, you might ask?
It was supposed that those events occur at the end of time. Thus, a linear timeline could look something like this;
Marathon-> Marathon2-> Marathon Infinity corrects defects in the M2 timeline that caused the Chaos beings to be released from Lh'ownons' sun ->
->WMaiD occurs-> Rubicon occurs-> [whatever else until the end of time] ->
->concluded by the end of time, and Durandal's realization in the M:inf endscreen that the player is "Destiny".
That's my perspective on it. Am I missing anything?
Regards,
-Blayne