Hardware-wise, there's five buttons on the device, two on either side of the bezel (that match old-timey watch buttons like Mode, Set, Adjust and Light). At the bottom of the case you'll find a switch that lets you cycle through the various read outs on the Nabu portion. This combination of low-fi and high-tech continues through to the power situation, since the timepiece will draw power from a cell battery that's expected to last between 12 and 18 months. The Nabu, by comparison, charges using the same proprietary pins as the original and needs re-juicing once a week.
My forearms are pretty big and I can wear a 50mm watch without it looking oversized on my wrist, but the Nabu Watch is still noticeably large. That bigness was part of the charm of, say, Casio's G-Shock watches, and this is clad in similarly sturdy rubber. Then again, I can't imagine people being able to wear this while dressed in a long-sleeved shirt or other formal occasions. Still, it'll draw plenty of envious glances while you compete at LAN parties or while running a marathon.
Razer is one of the most beloved gaming companies in the world and its fanbase is as loyal and devoted as anyone could want. Owning its products feels as if you're a member of a super-exclusive club and the company has a great handle on what its users desire. I can imagine plenty of people within Team Razer to plonk down the $149 (or $199 for the more expensive option) without a moment's notice. On the other hand, I doubt the timepiece will have much appeal for mainstream buyers, who could get a similar-looking Casio for a smaller chunk of cash.