The iPad 3 adheres to the old saw in technology that there is magic in version 3. While it is true that this is in part due to how wonderfully rich the app ecosystem has become, from a pure hardware perspective, the combination of a 264 dpi display and a lightning fast cellular network is about as magical as the many reviews have claimed.
At HP, the ink and paper crowd was always obsessed with what was known as the "300 dpi barrier," the thought being that until affordable displays got there, there would still be plenty of room for consumers printing the stuff that wasn't going to get stuck to the refrigerator. From my perspective, the pre retina iPad had already eliminated that for most of the universe of printable disposable content, but this new display has killed one of the last bastions of the printed page: the mixed content (text & graphs), multi-column, full page (usually) PDF document. Just this weekend I was reading a Comscore report with a number of tables & graphs and for the first time ever, I didn't feel the need to print any part of it out. Incidentally, this was the market for the Kindle DX but unfortunately that device was never general purpose enough to merit its price tag.
And on the network side, it is hard to explain the improvement until you experience it. Or rather, it is easy to conceptually understand the impact of more bandwidth, and slightly less easy but still possible to grok lower latency. But LTE feels ever better than the sum of those two factors. Quite simply it just feels more immediate. Struck by what the cause might be for this, I spent a little time poking around the Qualcomm site and came across this paper (consumed on the retina display of course) that argued that startup time from a "cold modem" (one which starts from an idle state) is quite a bit faster on an LTE connection than on a HSPDA (3G) one (about 3X), driven largely by improvements in signaling. And while it is true that most tablets live and die on wifi (92% of data traffic according to Comscore is coming from Wifi connections as opposed to 25-50% for smartphones), I think the speed of this modem may be about to begin to change that particular "leave at home" use pattern.
In fact, for the first time since the launch of the original iPad, I am now convinced that we've got a fundamentally different platform for which a new class of productivity applications ought to emerge. Something like the new iPhoto but on steroids since it should go way beyond leveraging the direct manipulation interface to using both the resolution of the display and the network in new and unexpected ways. It's too early to tell but my money is on new types of collaborative applications that leverage the high pixel density to navigate large datasets and the realtime nature of persistent and lightning-fast connectivity to put the collaboration in environments where users have been forced on "batch" mode for compute resources. Architects, field folks, and even presenters at conferences are a few of the examples I can think of for starters.
Finally, it bears mentioning that the iPad3 will likely not remain the only entrant (nor even necessarily the dominant entrant) in the market now that it has defined the spec that everyone else needs to hit now that it has, at least in my mind, validated the category as more than a portable television crossed with a poor man's laptop.
I am sold. Down with laptops and up with the strokable slates!