The new build is numbered 13C62, just 3 builds newer than the last build which was numbered 13C59.
The first beta of 10.9.2 included FaceTime Audio and was build number 13C32. Subsequent betas brought the ability to block certain iMessage or FaceTime users. Today's 10.9.2 beta asks developers to focus on Mail, Messages, Graphics Drivers, VoiceOver, VPN and SMB2.
Developers can download OS X Mavericks 10.9.2 from the link below...