^^^ This! The fact is that as of now, since Bittorrent Inc. isn't making money off the service, the only imaginable reasons for the code not to be released are to hide security flaws or to avoid clones of the project. Assuming that it's just the latter - it's still not worth it, considering no one would trust a clone more than the original app, and the patches from the community would be very beneficial for the stability and feature-set of the service. The actual BTSync developers probably know all of that, so I'm just going to say - the biggest reason for me to want a FOSS BTSync is because I want to trust it.