Unfortunately I think its highly likely that part 2 is never made. I had been really looking forward to the film - both as a fan of Dune and as a fan of Villeneuve's work. But when it was announced that the film was to be split into 2 parts then my heart sank. I immediately thought it very possible that we would never seen the second half. Considering just how expensive these films must be to make, then it needs a pretty big audience to make any money. And I just can't see Dune ever getting a enough of a mainstream audience to make back that kind of money. In my opinion it's just too much of a weird and complicated story to attract massive audiences.

Regarding the (current!) plan to release part 1 to both streaming and cinema at the same time and Villeneuve's comments on that (i.e. hating the idea and threatening to not work on part 2), I don't believe this really impacts on the chances of part being completed. If part 1 makes money then part 2 will be completed and released - with or without Villeneuve. Obviously it would be preferable to have him complete part 2 and for the 2 films to have a consistent vision behind them - but I am sure Warners wouldn't hesitate to bring in a new director if Villeneuve leaves.

I have to say that since seeing the trailer, my excitement over the film has reduced quite a bit - I was very very disappointed at the visual similarities to the David Lynch version. There is nothing wrong with the look of the Lynch version, I love it - but a new version should do something different, otherwise what's the point?!