I used a color called "charcoal" for the grout. The flash of the camera really makes it look lighter than it is. Under normal lighting it blends in well with the rest of the tile.
I'm also very happy with how the pieces I fabricated for the front corners turned out. I used regular flat tile and cut it to size on the tile saw. Then the angle grinder was used to rough the pieces out to about 95% of the final size. A couple of different grits on the sander took it to the final size.
A couple of coats of polyurethane later and the cut pieces blend in perfectly with the regular tiles. They're not perfect, but they don't stand out in any way, which is what I was aiming for.
The backsplash is next.