Honestly the Wii-mote feels much more like a remote control with a Z-trigger, which exists in several products I own, including a presentation mouse/pointer device that's a bit more sleek.
The resemblance may seem uncanny, but then again, there are a ton of TV/VCR/DVD/Everything remotes out there that also look very alike.
This case has the potential to do some damage to Nintendo, but it should not by any rights. Any market share this stole was from fanboys and tech-junkies who insist on engineering any gadget out there to do something it wasn't intended to do.
Nintendo also had the whole Z-trigger thing with the N64, this really isn't anything more than a TV remote with an N64 Z-trigger on the bottom. I will admit not reading much into their remote, but does it also act using a positioning through Bluetooth to read movements?
Hell, I made devices that looked like that with legos when I was a kid as pretend toys, it's not some break-through design, and I'm surprised it hasn't already been patented elsewhere.