See, Zynk, there's another reason to stop using the old US numbering. It confuses people, even if you do add the (US) tag at the end. I can't force you to do anything, but it would make it so much easier if everyone called the games FF4 and FF6. There can be no misunderstanding of what game you are actually talking about then.
IMO, Tactics isn't part of the real Final Fantasy series. Sure it's got it's name, but it's not numbered and it's so different in gameplay compared to the other titles, so it's standing out a little on it's own. And I wouldn't count X-2 either, as it's just a direct sequel to a previous title, not part of the real series. But that's just my opinion.
And you know, the american version of FF4 is a slightly simplified version of the japanese original. They made the game easier and took out a bunch of items and monsters in the american version, nowadays referred to as "easy-type" (and the japanese original is "hard-type"), because they thought the game would be too hard for the american audience.. or something like that. But I'm sure you knew that
Anyway, I guess you can keep the poll as it is. Unless someone demands to be able to vote on FF2 and FF3 (the NES games, I never use the old US numbering), then just keep it going.