Important to remember, the Dephormation add on is a 'sticking plaster' that identifies and suppresses Phorm tracking, not a privacy/security solution.
If your ISP is using Phorm, the only effective solution is a new ISP and/or encryption.
For web masters - the other party affected - the solution is in SSL. For example, adding an SSL certificate to this site is essential to keep the interactions with users confidential. Otherwise, Phorm get to read anything you read, get to examine your personal messages, and could even (in theory) modify the site content on the fly.
You really do not want people like Phorm monitoring your communications, at all.