Those planning on picking up the HD release of Final Fantasy X and Final Fantasy X-2 may have a couple of options at hand when it launches. According to an ad on the front page of GameStop, pre-orders will receive a free "limited edition upgrade."
Unfortunately that's about all the info there is for now about the limited version, and your guess is as good as ours as to what content it includes. It could be anything from a soundtrack to some kind of in-game item. The ad only appears in some regions, so whether or not a limited edition exists may also depend on where you live.
Final Fantasy X/X-2 HD is due out this year as a single release on PlayStation 3, and as separate releases on PS Vita.