I reckon there should be three editions.
1) The bare-bones edition, for people who just want to play the game at the standard price for PS3 games. Should have a Ferrari (enzo/FXX/599) on the cover.
2) The second edition should feature a 'making of' dvd showing fans what the GT5 team have been getting up to. Some kind of GT5 book listing all the tracks with breaking and turning points for each track, throw in a keyring and/or a flash drive. Cover car would be Lamborghini (or Porsche if it's in there)
3) This would be the Pièce de résistance of the three. It would feature;
-Special tin version of the game with Bugatti Veyron artwork
-Additional car(s) (ie a special Polyphony tuned Lambo, Ferrari etc with unique livery)
-Production book with development photos & track layouts for the real courses featured in the game, complete with breaking and turning points.
-Making of DVD/Blu-Ray
-Keying/USB drive
-Special Gran Turismo 5 edition Logitech G27 Wheel
I ask you, what more could you want? Apart from a free car of course...
And does anyone else prefer tin special editions to paper sleeves that usually deteriorate or get squashed easily?