Dutch news coverage of this issue is with a lot of bemusement about those weird Belgians. It is really not taken that seriously over here. The fact that we always joke about stupid Belgians also is responsible for this.
As for a theoretical split up, where one part goes to the Netherlands and one part goes to France. Such a split up would mean that the Dutch would control 2 major harbours in Europe, Rotterdam and Antwerp. From a money standpoint this would be interesting, but I'm not sure the rest of Europe would be all that happy with this.
Also in history, Belgium has been part of the Netherlands, but they seperated from us, so I guess the issues that led to this might resurface if you merg Belium and the Netherlands.
So in my opinion the current situation, though maybe not prefect, is preferable (keep Belgium in one piece).