We've actually learned very little about it so far. We got Ghostcrawler admitting there's not 31 bosses, and a few other BlizzCon tidbits, but beyond that, what do we know?
The other day, Zarhym at least gave us a small hint or two, saying that the 5-man dungeons would be epic and essential to the overall fight against Arthas, that they would be separate content from the raids, and that neither dungeons nor raids (Thank Elune) would have vehicular or mounted combat (the airship battle will not be a vehicle fight, it seems).
Of course, that does give us hope, but doesn't get us to the meat of the dungeon so to speak. So I'm sort of wondering: What do you want or expect to see in Icecrown Citadel, both the raids and the dungeons? Are there certain bosses or boss encounters you want to see? What type of storylines would you think epic enough for the 5 mans? I'm still hoping for the completely ignoble, futile death of Tirion Fordring, but that could just be me.