Two things came to mind after reading the synopsis:
1) There seem to be a decent number of Popes in Hell. That was strange. I figured Popes would be... exempt. But Dante has some Popes in some of the deeper circles of Hell. That was a bit unexpected.
2) Of the three most horrible sinners, who are doomed to be chewed by Satan for all time, there's one who is seldom mentioned in everyday conversation: Gaius Cassius Longinus, or just Cassius to his buddies. He was the Roman Senator who plotted Caesar's death. It seemed odd to me that Dante picked him, because that meant that of the three most horrible sinners, two were involved in the death of Julius Caesar. The other, of course, was Brutus. The other sinner, more horrible than any other, was Judas Iscariot. No mystery there. But why Cassius? I think it's probably because Dante was Italian, and Inferno was written in the early 14th century. Maybe that's also why he didn't plug his website! I guess I can one-up the old man in that realm.
Other than those two things, I thought the story of the Pilgrim with Virgil was quite different than any other story I've read. It sort of reminded me of What Dreams May Come, only that was more of a story of a dead guy who wanted to go to Hell to find some one. Inferno is mostly just a story of a guy taking a really long alternate route to get past some unholy beasts. And that's another odd thing: how come Virgil could get past all of Hell's creation, including Lucifer himself, but say "Hey man, I can't beat that leopard for you. It's just too much." Where's the logic in that? Ah, symbolism, how you defy me yet again.