Other that the normal 07 Vs 06 GT differences, these are the differences which I found thats are different in sti form .... other common sti goodies remain the same.
STOCK
MY07 Sti Vs MY06 Sti.
Black cars had mixture of charcoal or silver rims Vs All Black had Charcoal.
Brembos Vs no Brembos

Sunroof Vs no Sunroof
Sti embroidery seats Vs no Sti embroidery (supposed to have but 06 got ripped off)

Short shift felt looser VS tighter
Lower Arm brace Vs No Lower arm Brace
Claimed power 194 Vs 200

Headlining Light Vs Dark
Stereo and door trim Dark grey Vs Gun metal
Seats less bucket Vs More Bucket
Leather slightly lighter Vs Darker (leather qual also looked bit better in the 06- not biased

Full leather alcantara seat Vs leather alcantara with suede inserts
Door trim leather Vs Door trim Suede
Light headlining Vs Dark Headlining
#/300 Number badge plate on engine cover Vs below gear boot
Spec B dash plus sti insignia VS Full red dash
Poxy SVM sticker on boot of car Vs No svm sticker on boot
License plate frame Poxy puffy china Sti sticker Vs no sticker
Rear boot local Sti badge on left Vs Jdm STi Badge on right
MY07 and My06 tb STi versions
Sexy Vs Sexy