Not to bump my own thread, but for those who have not yet seen the PbP document:
Ability Scores: d20 style (+4 at 18), which I am pleased to see for continuities sake alone.
Notables: Adventurers (PCs) cannot have a stat higher then 20, monsters and gods, 30. No reference to a BAB, or level based mechanic in check or combat discussions. Stealth and perception discussed as general actions and ability checks, jumping depends on your strength score and does not involve a roll. Save for each ability mentioned (pretty easy for Str, Con, or Dex, harder to see how you decide on which mental stat is relevant). No "auto-success" in the section for players.
Hit Points: Con+HD. Roll HD for each additional level or use con mod, whichever is higher. (found that clever).
Recovery: Old School 4E: You get HD and can run them down, during a rest, with a healing kit. Here you add the con mod. (again, clever). No second wind. Long rest seems to be 4E style. Which is my only real quibble.