This is nice. The venerable Microkorg is still a great little synth, and they were wise to keep all the strong points and improve on the weaknesses: I'd say that the big news is the doubled polyphony and the screen to improve the usability of the matrix interface. Also, the keys are not diving board like the OG, but piano-shaped like the MicroKorg XL+, which has a much better keybed (within the limits of microkeys of course).
It remains to be seen what the sound engine is: did they just keep the original one and double the polyphony, or is it a different one? The 8-voice polyphony also reminds of the XL+, but that engine is usually considered less good than the original.
They say explicitly that the vocoder engine is new, with more features like autotune and harmonizer.
There's also a whole new loop recorder, more banks and memories, more effects, etc.
And of course, this being Korg, the unescapable limited edition color variations.
All considered, this looks like a sensible upgrade and definitely a better job than the KingKorg Neo, which is just a lazy repackaging of exactly the same old thing, minus its best features (5 octaves and real tube).
Who knows if it will be as successful as the original, though I doubt it: the OG was revolutionary and unique in its own way, while this one will enter a marked flooded with cheap small synths...a lot will depend on the price. We'll see.