Does anyone know if CD Projekt / GOG intend to make the Witcher 3 available for pre-loading when it gets closer to release day?

Probably

There was a pre-load when Witcher 2 came out, so I'd expect the same from the third game. I seem to remember being able to download most of the game a few days before release, but I'm not 100% sure on the time frame (it was four years ago, after all).

i dont have a perfect memory either but i seem to think it was two days prior and only a few megs on release day?

here's hoping

Yes.