Not so sure who they are calling "mainstream riders", but unless Harley-Davidson is some new tech speak for "completely recharges in seven minutes" this is destined to remain a novelty.
The .75-1 hour recharge time might just work for the bar-hopping rider if the bars offer charging stations.
Otherwise, I can't see how the current (pun intended) electric bikes will ever make it with riders who consider 130 miles as "just getting started" on an afternoon ride.
Though the term "mainstream riders" does probably encompass those who log less than a hundred miles a month, as they may be the lion's share of bike owners on the books. For instance, does anyone else notice a seemingly disproportionate number of cars on the road with Harley stickers? To me this would indicate ownership/brand loyalty may be more important than actual use to many of these folks. An electric bike might be a good fit for these owners.
Thinking further along the lines of how to charge a battery more effectively/efficiently from the standpoint of riding cross-country, touring, iron-butt riders, etc. I cogitated a small diesel generator being a bolt-on accessory (or design as a hybrid) that runs automatically to charge the system, whether the bike is rolling or parked. This way it might only need a twenty minute charge to "top off the electron tank" at the next break point.
It does seem to be a well packaged design. It looks good and brings electric bikes to another segment of riderdom. Motards, sportbikes, and now cruisers are represented in the plug-in motorcycle marketplace.
The toes are in the water and it is just a matter of time before these designs are distilled into forms which will eventually drive nails into the coffin of what we have come to think of as the traditional motorcycle. Electrics have potential (another pun) to offer a lot of advantages, but the disadvantages of high purchase price and necessary recharge time will need to be overcome before they are much more than a novelty, as Meriden wrote, for riders who want these to replace our dino-juice powered steeds for long days in the saddle.
Kudos to HD for the time and effort they have put into this. It is nice to see them taking the reigns to position themselves as market leaders offering new technologies.