The PS3 version is tracking above Mass Effect 2 in the same timeframe (when mass effect 2 was 8 weeks from launch, it had 99K pre-orders or something like that)
FF is far more popular so it WILL get a bigger boost closer to launch through huge marketing campaigns.
PS3 version could launch to 600K, with 360 version at around 300K = 900K total for the NA region alone
All hail the KING, Andrespetmonkey