For that matter, given how little we actually know, isn't it possible that these sample names/traditions/organizations/whatevers are just that--samples? For all we know, the wizard picks from a variety of "talent trees," schools of magic, or some other means of dividing powers, and these names simply refer to some organizations that combine them?
In that respect (and I think someone else may have suggested this), the Iron Sigil then becomes the wizardly equivalent of a god, such as Asmodeus. Worshipers of Asmodeus (using 3E as a baseline) tend toward LE alignment, and have access to domains X, Y, and Z. Similarly, wizards of the Iron Sigil tend toward blah personality, and have access to orb spells of effects A, B, and C.
And just like clerics need not choose from the default list of gods, unless the DM decides to use them in his campaign, wizards need not choose from the listed traditions, unless the DM decides to use them in his campaign.
Obviously, I have no way of knowing if this setup is how they're going. But I think it's no less feasible than anything else, and the fact that it's at least possible just goes to show how little we actually know.
(I can say, though, that if these traditions are, in fact, optional, or merely represent a few choices among may, that I wish the article had made that fact clear. It would have prevented a lot of fretting.)