It's when you start adding elements not in the original capture, It's no longer photography.
I could not agree more, adding to the image changes it to photographic art; however, subtracting (the corner of a building, a flying bird, contrails, et cetera) is perfectly acceptable. Obviously anything you can do it a wet darkroom, you can 'legally' do the same in photoshop.
So I can take a nice portrait shot and delete the everything but the eyes, it's okay? Or do I have to run that by the edit police to determine what is deletable and what isn't?
BTW, by deleting ANYTHING you are adding as well--you are adding space or order or isolation, etc. Like the construction crane behind the building example--that's not reflecting reality, it's portraying an enhanced reality that is meets the photographer's tastes.
Even just enhancing contrast is a change to reality, yet so many of you are saying "deviations from reality that meet my arbitrary criteria are okay, but everything else is taboo." That's a bit egotistical, don't ya think?