A new release of TrueCrypt is available. What’s new? This feature sounds really interesting:
Provides two levels of plausible deniability, in case an adversary forces you to reveal the password:
1) Hidden volume (steganography) and hidden operating system.
2) No TrueCrypt volume can be identified (volumes cannot be distinguished from random data).
Even if someone forces you to type your TrueCrypt password (with a gun pointed to your head as example…) you can type a password which will not unlock the whole system!
More details here!
The only new thing in v6 is hidden operating system. Hidden volumes and unidentifiable containers (files|partitions) already were in v4.