Sorry to come into this discussion a bit late (comparatively speaking).
During the past school year, which is just now ending, I came to depend on shooting Portra 400 with my Mamiya 7 to do most of my serious work. I shoot a certain way with my 7 that I don't with any other camera. I make images with it that I don't make with my digital cameras or even just film SLRs. How likely is it that Kodak C41 film is going to go away by the end of this year? I don't really care about B/W film from Kodak, because Ilford is committed to making B/W film and its future is secure for the time being. Color film, however, is super important to me.
To lose Portra would require me to change what and how I shoot, and I hope that doesn't happen.