According to this developer diary covering the next to last area in Dante's Inferno, Fraud and Deceit are where all hell breaks loose.
Of all the circles of hell, it makes sense that fraud and deceit would be the most packed. As Dr. House taught me, everybody lies, and when liars die, they become part of the tortured horde Dante has to plow through before his final confrontation with Lucifer.
Or maybe the devs are lying, and you'll just wander through without so much as a scratch, which would be a bit of a cop-out, but endlessly entertaining.