I'll leave others more knowledgeable in such things to comment on the legitimacy of this, but one practical thing I'll note: the assertion on the site that Windows Vista/7/8 has support for encrypted disks is only half true. Quoting from Wikipedia [1] "BitLocker is available in the Enterprise and Ultimate editions of Windows Vista and Windows 7. It is also available in the Pro and Enterprise editions of Windows 8."

Since a lot of domestic users will be using Home or Home Premium versions of Windows, and as one of those users who uses Truecrypt for full disk encryption, this does not leave us with as easy a migration path as this site now suggests.

[1] https://en.wikipedia.org/wiki/BitLocker_Drive_Encryption