Microsoft seems to have a much clearer vision here and anecdotally I know quite a few people that have been Mac users for ages that have given up on iPads and bought Surface devices because they can use them to do real work.
What an iPad will absolutely never do is mimic an existing workflow. People who try to do that are going to hit brick walls fast. I wouldn't be surprised to see full-fledged programming environments on iOS in the next few years (and to see iOS itself open up in possibly surprising ways), but I suspect they aren't going to look much like the programming environments we're used to.
I'm glad people love their Surfaces. They look like great devices. And, yeah, I wish I could do web development more easily on my iPad. But I'm a technical writer and a fiction writer, do both professionally, and have used the iPad to do (gasp) real work in both fields.
And there are some fundamental reasons why I expect it to stay this way. Mainly that touch is a very low resolution input mechanism but also that Apple has utterly failed to create a healthy market for sustainable professional software businesses.
What’s real work?