When someone is typing an answer, the OP (and only the OP) could view something like this:
This would tell me if someone was answering my question, and would be an indicator of whether I should hang around with the page open, or just close it and check later.
Related, not duplicates:
"User X is writing an answer" - banner to appear when another user is writing too
Because they suggest everybody could see a list - rather than just the OP and some animated bubbles.
It's been pointed in comments, but what if I start writing an answer, and go for lunch. OP might wait a while for me to eat my steak and come back to answer.
Plus, where's the added value? I don't see any advantage to this, there's already a notification system that alerts me when there's an answer to my question. I wouldn't wait on the page for someone to write an answer when I can go navigate the site, read/answer other questions and be notified when the answer is finished.
I just don't feel like such a feature is worth the development cost/investment.
Let me see if I understand the rational for this feature request. People who ask questions are so impatient that they need an answer immediately. If someone is in the process of writing an answer, the OP needs to know this so that they can keep clicking the refresh button until they see the answer.
My advice would be to be patient and check back the next day. If you want, you can install something like SENotifier, which will give you a notification once someone answers the question or leaves a comment. I'm sure you have more productive things that you could be doing while you wait for an answer; there is no need to stare at the question page while you wait for a response.
