SmartThinker's User Profile module will take care of your profiles and possibly your Friends/Groups needs. Throw in their UserGroups and Calendar and you're most of the way there.
DNNFusion's MyProfile gives you the "MySpace" setup almost directly, and there are several add-ons that work with it.
BizModules.net does Ultra-Media and Ultra-Video galleries that may meet your download, documentation and training video needs. We use the repository module for those, you might try that first.
Forums it's tough to beat Active Forums, by ActiveModules. Unless the basic DNN froums work for you, that would be my next, and only, choice.
There are any number of third party announcement modules, but the built-in one isn't too bad now. I have a preference for Invenmanager's Advanced Announcement, but not so much that I've bought it yet. :)
For the FAQ, the FAQ module may suffice, try it. Otherwise, ZLDNN does Advanced FAQ, which is the only one I've looked at but is really complete.
Not sure what you mean by Developer API, so I can't help you there. If you're thinking of a WIKI, I've never found one as capable as the PHP versions, and I'm not a big fan of the DNN Wiki module, at least not yet.
Hope it helps,
Jeff