Well, I guess I'm the first to get mine....advantage of being in Canada and working from home, I guess. Here's the unboxing. Build quality feels solid, lots of rubber on the bottom to keep it from sliding around. Layout will take a bit of time to get used to, especially for the left hand.
I haven't spent much time actually using it--plugged it into my linux machine and it basically worked as expected.
The only thing I'm not totally sold on is the angle of the enter key. I suspect they're intending it to be pushed with either index finger, but I think it would be better to have it sloped like the spacebars. Only time will tell, and maybe they'll offer that as an option if it catches on.
Edit:
1) I've uploaded a picture with a hand on the home row as requested. For reference, I normally wear XL gloves. Also added a picture with the capslock/numlock turned on. It's hard to do it justice in a photo but it's a nicely subdued blue glow that shines through the black keycaps. I like it.
2) I should point out that I ordered the 109-key version for flexibility but asked them to swap the 105th-key equivalent (above the tab) for a "Del" key like on the 104-key version.
3) As Gerk points out below, the enter/backspace are swapped from what they show on the website. If using the index fingers I suspect the version on the website (with backspace between the spacebars) would be better. I have a feeling I may end up swapping the shift and ctrl keys on both sides and then making the right "ctrl" key a duplicate "enter" key. As far as I can tell the shift/ctrl keys are the same angle which should make this a trivial change.
4) For xsar, one of the dip switches maps the left spacebar to "alternate". This should allow arbitrary remapping of left/right spacebars.
5) No user manual or drivers was shipped with the keyboard, which is unfortunate. I assume they'll be putting it up on their website.
It's definitely going to take some getting used to the layout of the keys that have been moved, but I think the curved horizontal rows will turn out to be a really good idea.