The more important of the two is "How can I give feedback about LiveJournal?" I honestly wouldn't know how to give it if I didn't hang around support. We have a FAQ for suggesting new things or improvements. We have a FAQ for giving feedback about advertisements. But yet, there is no FAQ about giving feedback in general. I think this is very important to have, so that users know who to go to with concerns and just general feedback that they'd like to get heard by the right people.
The way to send in feedback that I know of is feedback@lj. I wouldn't know it exists if I 1) didn't see it in Support cats and 2) sometimes it comes up in news comments. I can see that the email address is mentioned in the profile of lj_feedback - a community with barely a few thousand watchers - and not much elsewhere. I ran a site search for "feedback" and came up with /feedback - which doesn't mention feedback@ at all, and doesn't seem to be linked anywhere. :) If LJ really wants feedback from its users - and I'm continually assured that LJ does - then the proper ways of giving feedback need to be documented and appropriately promoted to the users. As it stands, it almosts seems as if the feedback channels are being hidden from users.
This FAQ would be most appropriate under cat-about, and could also include information about how to report bugs (open a support request), link to how to make suggestions (as it's different from generic feedback) and any other related information.
The other FAQ I want to suggest is a basic FAQ on
(I note that FAQs #104 and #148 still call My LJ "Portal", someone might want to change that.)
I'm not really familiar enough with the FAQs to attempt writing one or two yet, I'm afraid. ^^; And I'm not sure if I know enough about feedback in particular to write a whole FAQ on it in any case. As much as my stress levels and experience allow, I can try helping with these, if someone can make them happen.