Does wordpress meet my requirements?

Do you define WordPress as ww.wp.xz.cn ? WordPress is a CMS but themes and plugins on ww.wp.xz.cn are recommended for functionality of your requirements.

There related but not exactly the same — this explains the differences:

http://en.support.wordpress.com/com-vs-org/

Sounds like you’ll want self-hosted (.org) most likely.

Yep, those are pretty straightforward and common features. Some will be built-in to some themes and there are plug-in for others (like forums).

Themes here: http://ww.wp.xz.cn/extend/themes/
Look for responsive themes that are recently updated, also look at support (some have their own forums, others get well supported here)

Look at buddypress for forums: http://ww.wp.xz.cn/extend/plugins/buddypress/
There are likely others that would work too.

This page lists a lot of good resources that may be useful too:

http://codex.ww.wp.xz.cn/New_To_WordPress_-_Where_to_Start