Coldsweat wrote "Question - Does anyone ever use the display in their lenses??".
I know that I do, and I do so regularly. Think of any situation where your AF might be wrong or off like in low light, in low contrast, where there are many reflections, with many subjects at different distances close together, etc. etc. etc. This distance indication is a quick check that is required then (using the Depth of Field Preview Button on your SLR often is much too cumbersome then).
So I think that a "digital display" could be a real assett on this lens. Just like the distance scale on ring-USM lenses is usefull.
After thinking about thing part of the 'rumor', I hope that this new "display" will also give us back some form of the Depth of Field Scale that once was common on SLR lenses. That would even make this desplay more usefull. The FD lenses Canon had for the 35 mm SLR's also had them, and I loved that - together with many other users.
Think of Landschape photography, (occasional) Macro photography, Still lives, when you want to preset a Manual Focus distance in combination with a specific aperture for specific circumstances, etc. etc.
The new "display" should not be just a gadget to let the new lens underperform where it counts.
As others have written so many times in this and other threads, the main requirement for the new 70-300 non-L is
(1) better IQ than the present 70-300 non-L (despite what some believers keep repeating about their lens: there is almost unanimity about its IQ being bad); and
(2) much faster AF speed so that it is reliable at least around the house with playing kids, dogs, etc...
In that respect, nano-USM has a promise to keep based on the EF-S 18-135 mm. Let us see what AF speed Canon has decided that the nano-USM technology may deliver in an EF-lens for the intended buyer population ......