Price aside, this is a worthwhile upgrade simply for the ergonomics.
Glad I'm not the only one :-)
Given that two-hand holding is the norm for paper books I would say single-hand holding isn't a terribly important spec for an e-reader. Maybe it's desirable for some, maybe not. I would definitely give up a little bit of single-hand holdability for a larger screen, someone in thread above pointed out the 8" Bookeen Cybook Ocean, which at $180 looks like a good Kindle alternative: http://www.bookeen.com/en/cybook-ocean
I object greatly, and think that single handed holding is an extremely important spec. Far more important than some silly touch-screen.
But like books, we are all different. So I hope you enjoy your e-reader however you choose to read it.
It's not.
This then allows me to squeeze part of my hand/fingers between the cover and the Kindle and doesn't get too tiring.
I often complain about it, and this Oasis appears to be an upgrade, but I have the same problem with books as well. Adding the physical buttons in is a nice feature that I've missed from my earlier Kindles, as it at least means I won't have to move my hand while my Kindle is precariously balanced on the aforementioned finger for every page turn.
I hope this creates demand for a paperwhite attachment / cover that will achieve this same ergonomic design for those of us that don't feel like forking over that much money after only just buying their paperwhites.