All retina display means is 326ppi for small devices. Almost all of the other latest devices have well over 400ppi. You can argue that that many ppi is overkill, but it is still much better than the iphone's retina display. It's just another gimmicky name to make it sound better than it is.
As for the phone itself, I honestly can't see why anyone would buy it. There is literally not one thing that is any better than the latest (and cheaper) nexus, xperia, htc, galaxy, or motorola.
And I know this is missing some of the facts, but I found it pretty funny...
http://i.imgur.com/Vge3M7S.jpg