+1 for Sphinx. For me, it's crucial that code and documentation are kept closely together. As in, changes to the code and the related documentation go in the same commit. In my experience, that's the only way to keep them in sync. Sphinx works great in this scenario, can output the docs in many different formats, default HTML output has search built-in etc. It's cross-platform (although I've used it on Windows and Linux only, I'm pretty sure it works on Macs as well).
What happened with Dragon's NASA COTS demo missions 2 (ISS fly-by) and 3 (full cargo mission)? According to their launch manifest these were supposed to happen in 2011.
I too think that launching Android, more than anything, was a defensive (if not desperate) move. Apple would have locked Google out of mobile search sooner or later.
And that makes Android's success even more amazing.
I am afraid that it's #6. Sad but true. Personally, I've never owned an Apple product, but sometimes I have a feeling that Mr. Jobs has more to do with my Android phone than anyone else (of course Google ripped off iPhone, but that's life).
Open source, not too difficult to configure. Written in Java, requires Tomcat (or similar) to run. I think Android "organization" within Google uses it.
I have some issues with gerrit... it's giving a very limiting experience in my opinion. You cannot upload branches / patch queues. Every commit will be a separate review item. It's search and api also have lots of space for improvements. It enforces a workflow, rather than being just a transparent "let me scribble something on your commit" tool.
Then again... I looked for something better and could not find anything :(
This is good stuff, too: http://johnmacfarlane.net/pandoc/