The current panic over TrueCrypt is overreaction.
The statement that “TrueCrypt is no longer secure” is strongly misleading. TrueCrypt did not magically become insecure overnight. Either it was insecure before, and this has just been announced publicly, or it wasn't insecure before.
What has changed is that the manner in which the TrueCrypt project stopped casts some suspicion that TrueCrypt was insecure in the first place. However, without knowing in what way it is insecure (assuming that it is), it is impossible to know for sure what to do about it. Is there a fundamental problem such as the key being hidden in randomized parts of the disk? Or is it only some specialized feature that hardly anybody uses that is vulnerable?
What has also changed is that TrueCrypt is no longer maintained, meaning that if new security issues are found, they will not be fixed. This alone is a reason not to use a software package. However, given that TrueCrypt was pretty popular, there's a good chance that someone will take over the maintenance.
I recommend doing nothing over the next few weeks, and see how things evolve. If it looks like there is an emerging successor, gradually edit posts to switch to that successor. If TrueCrypt seems headed for abandon, comment on posts (constructively, by preference — recommend something reasonable instead). If a major vulnerability is discovered, edit posts that would make people susceptible to that vulnerability.
Note that I do not say that as a TrueCrypt enthusiast. Indeed, I do not recommend using TrueCrypt in most cases — most people should their OS's native mechanism instead (Bitlocket, FileVault, Dm-crypt/eCryptfs). But there's a difference between not being a fan and going on a crusade (I don't go commenting against Windows on every post that uses it, after all).