There's no way he would've changed his mind about making this for wii and change it for PC use only. Seriously, this is every game designers DREAM of having there games not only being played in the PC but worldwide on the WII. I would definatley stick to the wii.
This mode of thinking only works under the assumption that a game
must be platform-exclusive. (Which it needn't be. EG, World of Goo, Braid, etc.)
Edit: And I realised not many people are using the name Nifflas anymore (Like this article) They're using "Nicalis" more. Nifflas is 'growing up' in a way and its a dream for him and we should be proud.
But, um. I haven't seen anything indicating that Nifflas will continue working with (have games published by) Nicalis after Night Game. (Although this is entirely possible.) Any sort of pride is tainted by the knowledge that large-scale recognition is being shifted from "Nifflas" to "Nicalis", and that the association between the two isn't permanent.
If NG is released with just the Nicalis branding up front, it won't make much difference sales-wise than if it said "Nifflas", since most of the WiiWare market won't be familiar with either. But in the future, if Nifflas's games are published by other companies, he won't have the brand recognition that he would if all his games were released with his name immediately apparent on them, and people unfamiliar with Nifflas won't be drawn to his games by a past familiarity, and each game will be forced to be sold on its own merits. (Not an altogether bad thing critically, but not good financially.)