This document discusses methodological questions around studying persuasion in serious games. It notes that games are being used for various non-game purposes like health, education, and advertising. It raises questions around whether this amounts to manipulation of players or exploitation of game qualities. It also briefly outlines some frameworks that could be used to study serious games, including levels of analysis models and considering different player attitudes and playing conditions compared to traditional games. The document calls for approaches that consider both game structures and player reception to better understand serious games.