I just finished reading "The Whispering Cairn" myself this morning. I'm kind of late but Ive been rather busy with the Shackled City campaign.
While the initial plot hook doesnt ease you into the adventure as well as the one in the Shackled City did, the adventure itself is "a work of art" IMO.
I loved the ancient tomb exploration feel which also reminded me of greats like the Tomb of Horrors and Mud Sorcerer's Tomb. I had also almost completely forgotten about the obscure Wind Dukes, The Rod of Seven Parts, etc. It's nice to see references to another great adventure of old.
Diamond Lake looks like it will be great, and best of all, different setting. I like its corrupt slant.
Overall, I have to say this is an excellent beginning to a potentially great campaign. The pacing is perfect. Im glad we didnt get flooded with a too many NPCs from the start, I'm sure we have yet to meet many more great personalities in future installments.
Erik (if you read this)... A truly outstanding low level module and campaign starter. Im definately looking forward to more Dungeon adventures from you, be it "Age of Worms" or not. Life as an editor may be too busy, but any more adventures from you would be very well received by the looks of it.