Have posted about this before, but the key thing about digital slides now is that they are made from glass slides. Thus, you can't bypass any step of normal pathology diagnosis now by going to digital images. It is far quicker to just look at the slide under glass and then make a diagnosis then take said slide, scan it in, and then fumble with the massive image in an interface. The only ways, at least for now, that it shows promise are with consults (scan in your slides and send them electronically to an expert - saves transport time and $$$), frozen sections at remote sites, and possibly for slide archiving.
Pathology slide images are orders of magnitude more complicated and large than digital radiology images. One slide is many GB.