Pro cameras - where you shoot in RAW mode, and do post-processing later at home on your gorgeous widescreen IPS display, curate it, and then upload to your favourite hobbyist sharing site (Flickr, SmugMug, etc). That doesn't really lend itself to requiring a wireless modem.
I can see integration of GPSes into DSLRs - geocoding is a hotly requested feature particularly by hobbyists, but modems?
The absolute top-end Canon cameras have WiFi dongles that can wireless upload photos as they are shot to a storage unit. This is really to facilitate quick review in a studio setting - you aren't tethered by a wire, but can review the photo on a big screen very quickly after a picture without popping the memory card.
But while you're out and about? It seems pointless. The uses of a pro camera do not include "hey guys I'm at a pizza place. Look at the size of this sucker!", which is really where a 3G modem seems useful.
But I agree, this isn't a huge deal.
Dave was specifically calling out a line from their ad campaign, saying that real cameras don't have ringtones. He then argues about an entirely unrelated point, that cameras without data connections won't be terribly enticing.
Except that his original point is still there, and still is pretty dumb. Real cameras won't have ringtones, because placing a call to a camera is a bad feature, that nobody wants.
A camera that has a wifi radio, though, is a cool feature, which everyone wants, which is why Nikon made a wifi attachment for their pro DSLR line. It's called the WT-4/4a, and they released it in 2007.
(Of course, being Nikon, they charge $700 for it, but that's another matter.)