I think that Blizzard did a great job in Icecrown. Some of the questlines are epic in feel. The zone looks really gritty and has a great atmosphere. The flying boats are cool, too.
And its mostly empty.
Almost everyone in my guild hit level 80 in Storm Peaks or, at latest, a handful of quests into Icecrown. Once at 80, the race to raid begins and questing is put aside. Have you tried to get together a group for the 5-man Icecrown quests? I’ve tried, but have been unsuccessful. Its too bad, because some of the quest rewards are awesome.
(note that many of those 5-man quests can be done by a group of 2 or 3, but a couple are tougher)
Its a shame that Blizzard put so much thought into the zone for so few to see.
Rogues – for pre-heroic gear try to do the questlines there to get the Severed Noose of Westwind, Shoulderpads of Fleshwerks, Bloodbane Cloak, The Darkspeaker’s Treads, Signet of Bridenbrad, and Vengance Shiv. All of that is good enough gear to start heroics with.

