Throughout the series, one will hear McKay call the Zero Point Modules "Zed-Pee-Ems." Saying zed instead of zee for "z" is a characteristically British, and by extension Canadian, articulation. It's a small detail but an important one for a multi-national group of people especially since the only English-speaking nation in the world that pronounces the last letter of the alphabet as "Zee" is the U.S.A. All other 41 English speaking nations pronounce it "Zed". The English, Scottish & Shetlander (British) and Australian members of Atlantis (according to their uniform flags) should be heard to say "Zed" in the future, which would be their natural way of speaking. But since 60% of the English-speaking people in the world live in the U.S., and the show started as a U.S. project, it is understandable that most personnel in Atlantis will pronounce it "Zee".