What a thread!
The same question has been with me for a few months now, and has affect both my photography and my writing. I don't think that I put so much of my 'soul' into my paid writing or shots as much as a joyful professionalism - something similar to a good motorcycle ride. There's a point to get across that should be done well.
But when writing for myself, or Herself, or shooting for my parents, I've tried to do something else, something more direct. Perhaps a mistake, as i no longer have the frames that I put my ideas into, I've dropped patterns.
Then about two weeks ago I went out make images of the church where I'm getting married. In a way, it's useless for APUG - the B&W is digital, the 4x5 slides - light struck - but in making those images I figured out the directness that made her fall for me in the first place and that - on a good day - enters my writing as well. It's a pretty easy location to find, but about 10 meters off the road, and in a museum garden. Anybody can take that shot, and it'll be there decades from now - but it takes an eye to think about going to that garden in the first place.
That directness won't need to enter my paid writing - at the moment - though as a technique it could serve me well. That might be a crossover point between business and something personal - something more than the joyful professional, then. Or maybe happier, even. Dunno.