Ok, here we go. I've been playing GT4 for a few days now, and I can tell you that it is amazing. I prebooked it and picked it up on the 28th for 6500 yen, about $80 Canadian. Every other place selling it now has wait lists and its going for about 7800 yen, or approx $100 Canadian.
Best racing game I have ever played. The scale of this game is just immense. There is so much to do. The graphics are brilliant, though there is occasionally a minor fuzz that seems to be related to the sound. There are tons of tracks, 2 snow, 5 dirt, a bunch of different cities and real tracks, including Hong Kong, Soeul, the Nurburgring, and the full Circuit de la Sarthe!! Complete with or without chicanes on the straight. Sarthe and the 'Ring are just awesome to drive. There are so many cars in this game, however, many of the ones on varrious internet lists have been left out. The menus are more akin to GT2 than GT3, though everything is laid out in a logical manner. Tons of races as well. Missions, and of course B-Spec. Unfortunately, as I live in Japan, I cant understand the game completely so I cant really comment on B-Spec.
The gameplay is great. A vast improvement on the physics of GT3 and the realism is more evident in the way that the cars handle. The sound track to this game is large. think GT3 times 5, or so. Music from many different genres, and this is just the J version.
All in all, this game is a worthy successor to the serries. If you liked GT3, get this game. If you liked GT2, get this game. If you have a playstation and like cars and racing, get this game. Its awesome.
Well, back to playing before my holidays end on Saturday