

By reverting the state of the OS after each use either by using a live OS without permanent data storage or a virtual machine with non-persistent storage you avoid long-term storage of the information which could lead to your identification.

Furthermore Tails is able to separate unrelated traffic into different Tor circuits. If it is possible it is transparently redirecting all traffic to the Tor network regardless of used applications and their possible vulnerabilities. OS like Tails makes information leaks less probable by not allowing clear-text communication.To be more secure you should use a complete secured operating system with unified configuration so that you cannot be identified when versions of various parts of it get revealed.

The Tor Browser Bundle already solves this for the included software (Tor, Firefox, Vidalia Bundle). It is advisable to use least possible customized software.
