Interestingly, the bottom of the keyboard is actually flat - so it won't hug your lap as one might have initially presumed. However, the arched keys were comfortable to type on and, overall, the feel was described simply: "great".
On the downside, if you don't like smudging and quiet keyboards, the Arc is probably not for you. It also lacks the colour range of Microsoft's Arc mice and, inexplicably, the included USB dongle doesn't accommodate both peripherals. Still, if you want a functional keyboard that actually complements your decor, the Arc might be worth looking into. [Microsoft and DVICE]