So, this went down today (or yesterday in Japan).  Some fabulous stuff here.  Check it out:

Hoping for a CD release or a nice HQ rip at the very least at some point.

Part 1 (Super Mario Bros.)
Part 2 (DKC &  Legend of Zelda)
Part 3 (Kirby & Animal Crossing)
Part 4 (Pokemon)
Part 5 (Smash Bros. & Nintendo staff talk)

Enjoy.

Only three minutes into the first video and wow.  Nice find, can't believe I'm just hearing about this now.

All together now, "Club Nintendo Reward."

Edit:
I took the liberty of adding series titles to Kenology's links.

Who'd have thought "Dark Overworld" from Zelda: A Link to the Past would sound so good as a jazz arrangement. Plus the Skyward Sword theme for extra greatness.  And as someone who has no interest in Pokemon music, that guitar and New Orleans jazz intro (with some cool funk to follow) sure is close to changing my mind. It may be the most fun arrangement of the bunch.

The arrangements are credited to Masanori Sasaji (笹路 正徳), whose VGMdb credits are a bit slim but has produced some of the bigger (and more respectable IMO) J-pop acts.
http://vgmdb.net/artist/5125

I jumped right to Pokemon, being a big fan of the franchise (and yet, not in love with the music generally). The New Orleans vibe was fun--conjured images of Snorlax in a white suit and bolo tie--but once it veered into funk, I was enthralled. This scratches me right where I itch.

Thanks for the links, Kenology; it's going to be a great night!

Adam, North America's Club Nintendo physical rewards have been shut down until May... a CD would be an awesome way to relaunch the rewards, but I wouldn't dare suppose a CD release would ever be a coin prize. It would make a fantastic Elite Status reward, though.

Wow, I'd never even heard about this.
Listening to it now, and liking it a lot!

I'm assuming Adam was talking about the Japanese Club Nintendo, which often has exclusive soundtracks.
Would be cool if they released it there.

Indeed, I'm not holding my breath. The past two years' Zelda soundtrack rewards are the only reason I'd even consider it a remote possibility. Europe recently got the Super Mario 3D World soundtrack, though... still probably means nothing for the NA side of things, but it's a step in the right direction.

Why would we ever get soundtracks?  They're clearly the most expensive thing ever to produce as a freebie.  Oh wait, actually they're not and I have NO IDEA WHY they don't offer them.

Wow, awesome. Hope those YouTube videos don't get pulled before we all have a chance to see them.

This is like a dream come true. First the Galaxy series, Mario 3D World, that elusive smooth jazz-style performance at the Nintendo 3DS show a few years back, Mario Kart 8 and now this? I'm thinking Nintendo has a love affair with big band jazz -- if they want to stop doing game consoles and pour their efforts into big band arrangements, I'm back on Nintendo's bus.