Drew had a couple of interesting comments on "IT" in his recent
AMA. These included that i) we are "not looking for a specific POI" and ii) "at this point it's unlikely you would recognize it for what it is, although it is becoming clearer day by day".
To me this suggests that "IT" is actually just a particular region of space. Which happens to be the home of or occupied by...something dangerous (mostly likely, intelligent, space-faring and dangerous, because otherwise it wouldn't be much of a threat). You could jump into the dangerous region, but unless you notice the threat, you aren't know that you've found "IT".