There are two popular trends in epsitemology today that, taken as avenues that may add epistemological insight are fine, but taken as the way to do epistemology are nonsense:
1) Evolutionary epistemology. Yes, our history and our genes will be relevant to how we know things and what sort of things we know. But some people want to go further and say, "Any confidence we can have in our knowledge can only be grounded in the fact that evolution has steered things so that our minds can successfully cope with reality, because, of course, only organisms that successfully cope with reality will survive."
The problem with that is you're grounding all your other knowledge on your theory of evolution -- but how do you know that's right? For instance, I reject your idea with my theory of evolution: Nature is perverse, and has assured that only the least fit creatures with the worst cognitive maps of reality have survived, by wiping out all of the most fit ones with earthquakes, floods, droughts, etc.
Of course I think the latter theory is dumb, but it certainly can't be rejected by pointing to the former theory, because that's precisely what's being disputed! So it turns out that we do, after all, have epistemological resources independent of counting on evolution to have weeded out bad ideas.
2) Formal epsitemology: Again, formalism can be useful, sure, but it can't take the place of "old style" epistemology. I can't find the fellow's web site now, but I ran across a guy who said, "There are two types of philosophy: formalized philosophy, and vague philosophy that never resolves anything."
And, once again, the difficulty with mistaking a useful tool for the subject ought to be obvious: A formal analysis may clarify one's thinking on a problem. But the formal analysis can't tell you itself if it does so! For example, let's say I tell you: "You want to know what beauty is in art? That's easy -- just look at the Pythagorean Theorem!" This is obviously silly, but the formalism itself can't tell us that! To see what formalisms are relevant to what philosophical problems, and in what way, requires a non-formal judgment.