Rated 4 out of 5 stars

Looks like it does the trick, with three caveats:

1) This will import your entire password database into keychain (but erase your entire Firefox password manager database!). Would have been nice to know that before I relaunched and saw that section black.

2) This will disable the master password feature in Firefox.

3) The only way to access passwords now is through Keychain. Would be nice to have a link to Keychain through a menubar option in the "Tools" menu or the Firefox Preferences --> Security --> Passwords section, since the Firefox password list is now empty.

Otherwise, this is a great utility to keep my password list in sync with my other Apple mobile devices.

This review is for a previous version of the add-on (1.0b1). 

Glad you find it useful. A couple of clarifications:

1) It doesn't erase the Firefox database; it just sits in front of it (it even falls through when it can if it can't find a match in the keychain). If you uninstall the extension, your firefox database will again be the active handler.

2) The master password still applies when you try to access the firefox database (but as I said above, this only happens when a match isn't found in the keychain). Obviously the master password doesn't make sense with the keychain since the keychain has its own password and the keychain data is not available to be encrypted with the firefox master password.

3) I'm surprised by this comment... the behaviour *should* be that the keychain passwords available to Firefox now show up in the password list. Not that this behaviour is very intuitive mind you, but it's just what happens when you provide an alternate password database for firefox. I don't know the magic incantations required to remove the Passwords button... Also not sure how to add a link to launch Keychain Access but if anyone knows I'm more than happy to add it. :)