In a word... YES
If you are planning to have the music mastered, it will make a ton of difference.
If you are just doing some tunes for fun, then I wouldn't worry about it.
Although the music gets dithered down to 16 bits anyway, you want to present the sharpest, clearest mix possible to be mastered and/or duplicated.
There are frequencies that just don't sound quite as good in 16 bit/44 kHz as they do in 24 bit/96 kHz.
It is possible to make good recordings in 16 bit... REALLY good. But, the quality in a 24 bit recording is MUCH better.
I know I'm not exactly giving you technical proof here. But, someone like sonusman could explain it much better.
If you want to hear what a mastered 16 bit recording from a Korg D8 sounds like, check out the my post in the MP3 mixing clinic for a link to mine and my partner's website.