Yeah, it's a remote skin, made by a third party company but fully endorsed by Nintendo. Uts got a black one as well, and I'm using the wrist strap that came with mine on my DS, which is also pink. We thought it would be a good idea to pick a couple up to help personalise our remotes until Nintendo gets around to releasing coloured ones, and at ten dollars each were in our budget.
Here's a scan of the disc art, Bounty:
The interior of the case it pretty much like a standard DVD case, white and with tabs on the interior of the spine for an optional second disc tray. Above the disc is an embossed Wii logo.
There isn't really much of particular note in the manual, that wasn't already explained in a control demonstration video we found on YouTube, though it goes over the various control movements pretty easily, with little thumbnail graphics. Uts was pretty happy to see Mr. Popo listed in the voice credits (most likely for the adventure portion; we already knew he wasn't a playable character), and I was happy to see that it listed the option to switch the characters' language to Japanese.