The anthropic principle postulates that our universe is selected for the presence of consciousness in it
This is, of course, a tautological argument.
Let us take the example of some flower which appear white to us, but which actually have stripes and other patterns in infrared colors, visible to bees. To us, at least up until the last century, the flowers are white; to the bees, the flowers are striped; now that we have instruments capable of registering infrared light, the flowers are striped for us as well.
With this in mind, let us ask: what assurance do we have that the universe does not possess all kinds of attributes, patterns, objects, entities, etc., that are not observable by our senses (or the instruments we have invented to extend our sense-perception)? The answer, of course, is none: to use Rumsfeld's schema, we have no way of even beginning to assess the size of the unknown unknowns.
Which means, of course, that what we call "the universe" is nothing more (or less) than "the portion of the universe knowable by us". And this is necessarily always the case.
So, there's no need for a rigorous definition of "consciousness" in this regard; what is relevant is the limits of our sense-perception (as extended by whatever technologies we have developed.)
And, the criteria to judge whether or not a configuration of the universe has consciousness in it is: yes. Since we're talking about it, it does. If it didn't, we wouldn't be capable of raising the question.