Yep. That indeed must be O.
Fun part is...after that, the upper/lower case of method and property names do not matter.
Code:
var fso = new ActiveXObject("Scripting.FileSystemObject")
var fl = fso.OpEnTeXtFiLe("c:\\inetpub\\wwwroot\\junk0.html");
Works just fine. As does
fso.opentextfile or
fso.openTextFile or whatever.