Among the articles I’ve read on the topic, I think Jason Snell’s ”Searching for a good reason to remove the headphone jack” on Six Colors is the best.
I’d like to add extra emphasize to the way a (so far hypothetical) removal of the 3.5 mm jack would impact the audio and music business in a bad way. In recording studios all over the world, there are people connecting their phones to big, expensive mixing consoles. We do this for instance to be able to listen to reference material when making a recording. Same is true in the live sound world. In PAs everywhere there are phones connected to the Front-of-House mixers being used to play music that the engineer needs to calibrate the PA properly. So far this has been pretty straight forward, since every phone, every tablet and every laptop that I know of has a 3.5 mm jack.
So regardless of what (brand of) device people might use in your studio/PA, you can count on the 3.5 mm tele plug to be the simplest solution.
If Apple removes the headphone jack we will have a more stressful work-environment, with more crap to keep track of and more adapters to loose.
So please, say it isn’t so.