Couple of details which I think help put this route in to perspective for the non-climbers:
1. Caldwell, one of the best climbers in the world, has been working on trying to climb this since 2007--the combination of longevity and perseverance is hard to match.
2. The easiest pitch (out of 30 total for the route, a pitch being a rope length usually between 100 and 200 feet) is 5.11 which is pretty hard but the real kicker is that there are 5 pitches 5.14 and of those 2 are 5.14d which is was the upper limit of difficulty until the last decade. Most 5.14 routes are short single pitch routes which take pros sometimes weeks or months of practice to climb. Not every pro can climb every 5.14 since they are dependent on a high degree of specialization. There are 10s of 5.12 and 5.13 pitches thrown which makes the whole project together the hardest complete free route in history.
Essentially this route is an order of magnitude harder than anything which has yet been climbed in rock climbing.
I'm kind of amazed to see this much press (multiple NYT stories, new channel coverage) on a big wall climb (or any climb not involving someone dying) and can't really remember something equivalent.
This is a pretty good article with more specific details about the climb: http://www.adventure-journal.com/2015/01/why-is-climbing-the...