"Is BitTorrent Sync open-source? BitTorrent Sync isn't open source software, and no announcements have been made to indicate that this will likely change."[1]

[1]http://forum.bittorrent.com/topic/17782-bittorrent-sync-faq-...

My thoughts exactly. I'm certainly going to be looking at other options, including BitTorrent Sync. As useful as Dropbox may be, it's something I'd be willing to do without if this is true.