Testnet is live. You can read the announcement here. OP will be updated now. All testnet releases are in signed binary form right now - so run in a VM for the security conscious. All source code will be made free and open-source close to the launch of mainnet. As stated elsewhere, but repeated here for visibility (things do get buried), mainnet will be launched 1 week from testnet - so on Wednesday, February 3rd, 2016. This of course depends on testnet and if no serious bugs are found, the schedule will stick. More information will be posted as it comes in. I'll make sure to update people on all the platforms.