"One of the best games of recent years", yep, it surely is !

But I would precise that it isn't just a "throwback to the old 8-bit video games". Well, it is, but not only. Cave Story is really an awesome game, and despite the graphics and the musics, he's really modern. Because the game is made by only one person, the whole is truly consistent. Aesthetic, music, gameplay, level-design, universe, scenario, dialogs, etc…
I initially wanted to buy the Wiiware version, but I changed my mind. First, because I played it three times on PC (one time with the normal ending, then the secret ending, and finally another for the fun, and to try some secrets weapons). But also because I've tried the demo, and… Well, I agree, this is a really great portage. It's beautiful, the gameplay with the Wiimote is well done, and there are some interesting bonus mode (play with Curly, Boss fight, time trial…).
BUT, I think the original is better, though. :/ First, because it's the original version. The game have been made by Pixel, a single developer, and that's why everything in the game is coherent. Cave Story is like a door in the mind of the creator. The remake is from Nicalis, a great studio. They have done a great work, but they haven't succeed to recover the spirit of Pixel's work. The musics, especially, are totally transformed. I like remix, but the new music from Nicalis are really too different from the originals, it's change completely some ambient. An example ? The main theme :
Original version
Wiiware version
Also, some other musics in the Wiiware version are totally missed. They lost all the essence of the original soundtrack, which is awesome.
But there's more. The translation is also changed. Well, Nicalis wanted to do a more faithful translation that the fan-made one. But… Some sentences of the first english translation was become famous ! Like "Huzzah", or "Somewhere, a transmission", that became on Wiiware "Oh yeah" (-_-) and "Someone's transmission" (not the same strength). Also, Nicalis took the freedom to put some jokes in the dialogues, like a "LOL" in one scene. Well, maybe it's a good idea, but sometimes it can ruins the immersion.
And to finish, on the technically side, the Wiiware version isn't really great. There are problems with resolutions, and originals musics are in a really poor quality. Yes, the Wiiware version include the original graphics and soundtrack. But that one is bad encoded, or compressed, I don't really know, but when I first heard it, it was hard. >< I so love the Cave Story's song, it's really sad that the soundtrack is so badly deserved in this remake.

But anyway, you have to choose an option in the start screen to switch between the "old version and the "new version". And during the game, to go back to the start screen, you have to… die. Yes, there is no "back to the menu" button.

That's clearly stupid, and in some points annoying (let's kill ourself, yeaaah, I have to take damages, again, and again, is there a way to die quicker ?).
So, finally, I would advise to choose the PC version. It's the better way to appreciate the game, and all its spirit. I don't think he needed to be "actualized". Even in a 8-bits style, and chiptune musics, he's really beautiful, and enjoyable. Maybe he's a little short, and sometime too easy (though I found the difficulty well dosed, and the final secret level is extremely hard), but he is indubitably epic.
Ah, and the 3DS version ? Well…

It doesn't just ruin the charm. It's also ugly.

Cave Story is a 2D games, with graphics made for be in two dimensions. Put it in 3D isn't doable without having a
disturbing result.
Developers, stop doing 2.5D ! 2D is prettier !
