It's funny how you change one letter and it goes from a wimpy sounding word associated with something small, urine, a penis or what kids yell when they go down a slide, to something that sounds pretty cool. "Zii" has all the positive things that Nintendo raved about "Wii" (which I actually forget, something about being short or something) but it isn't something an English speaker would make jokes about.
If they spelled it just "Z" then all us Canucks would call it "Zed".