I like the fact that Google Code is a free option for Mercurial hosting but, in the test project I set up I couldn't find a way to designate the repository as private.
Ideally I would like to work on a project privately until it is ready for the world to see and only then open it up to others.
Is there any way to do that on Google Code?
I'm pretty sure the answer is no...the whole point of Google Code is free hosting for open source projects. Open source projects by their nature are not private. If you are planning on releasing the code for free, why so worried about keeping it private? Nobody is going to care if you publish unfinished code...I mean that's 90% of the open source projects online.
Another thought...isn't Mercurial a distributed source code control system? Couldn't you just run the Mercurial locally until you are ready to publish, then at that point push it up to Google Code?