Just my 2 cents before I disappear off on my hols.
I think it depends on your definition of what you do. Are you an artist or not, depends on what you define as acceptable in changing a photograph to almost something that looks like a painting or a painter produces something which can be viewed like a photograph.
When 3D holograms take off as pictures what are the limits then, does that mean its the end of 2D photography because in a lot of critiques we make a point of adding depth to a photo.
In my mind the line is a meaningless concept as art cannot be defined as it is subjective and therefore eveyone will choose their own definition by available skill and time.
However, no matter what techniques we use to get to the final image whether film, digital, or graphics its the final image that we want to present to the populace is what counts.
Roger