Feedback:

- Autofocus on input field in modal windows after clicking "Follow a new HackerNews user".

- Remember my checkbox selection in the same modal window

- Favicon!

- Autofollowing e.g. "pg" could improve onboarding

- Design is not very content focused right now, I would probably switch the middle and right column

- Highlight found keywords in comment text

- Notify/show me if someone replied to one of my comments

- Modify title depending on what is shown (Right now following.php always shows "HackerNews users I follow" even when I have selected a specific one)