Including the word "phishing" in Firefox's UI is a bad idea. Most users won't understand the word; it's jargon. In particular they won't know that it's bad until it's explained, and most people won't bother reading any explanation. Thunderbird uses the terminology "scam" and "scam protection". "Fake" or "forgery" would also be better than "phishing". Any of these would make it suitably obvious that this is a bad, scary, evil website.
The warning already uses 'forgery' (with 'phishing' hidden and fully explained under a collapsed portion of the dialog) and once bug 340677 lands, it'll no longer exist in the pref panel either.
What about the Help menu item ("Report Phishing Website")? Will that be changed too?