It sounded like an American Bittern, had an angonizingly slow gait like a Bittern, stretched its neck high and pointed its beak skyward like a Bittern, was in the same boggy/marsh area as another Bittern; but it had plumage like I have never seen before!
I have concluded that this is an American Bittern displaying breeding plumage although there seems to be very little information relating to this stage on the internet.
editing note May 11, 2007: I found a reference today making mention of white, fluffy feathers sometimes seen on an American Bittern. In his book, Sand Dunes and Salt Marshes by Charles Wendell Townsend, 1913; chapter X; Townsend writes in reference to the American Bittern:
"...the birds have an interesting courtship display of soft fluffy white feathers which are ordinarily concealed, but which on this occasion are spread conspicuously on each side of the breast while the gallant cock-bird struts before the hen." source found online at: http://www.kellscraft.com/SandDunes/SandDunesCh10.html
There were two birds seen in the bog. Directly above is an American Bittern photographed in the same bog/marsh as the bird with the white spots.