ALL of those high end digital SLR's are a complete waste for shooting on the web only. If you intend to make prints of your work, then the EOS 1Ds or the Kodak 14n are "the best" currently available.
Don't forget a few thousand clams for
good lenses to take advantage of all that amazing capability. A $100 Tamron is going to make those cameras cry for mercy.
If you want some good reading by a true professional, check out
The Luminous Landscape