Gran Turismo 3, to me, is the ultimate way to get ready for GT4. I play it a time or two nowadays. Other than that, I'm typing up threads and replies for GTPlanet. But if you ask me, more GT3 is not for me. I often play Gran Turismos 1, 2, and 3. Why? I'm a GT Veteran. Have to get all tuned up and ready to play on game day. That game day will be me playing GT4 one month, then seeing the pack get OWN3D by my driving finesse the next month. Of course, I don't care about online play, so don't expect to see your boy John (me) online strapped into a Toyota GT-One or McLaren F1. I think you can be able to view online games, but I have crappy (but reliable) dial-up.
People will have their own opinions, but in order to get into the upcoming GT, you'll have to play some of the past ones. Gran Turismo 1 actually had some of the best menu music even if it was a little dull compared to today. Darin and I talked about this once on MSN Messenger. The TVR theme was probably the coolest one, with Aston Martin's theme at the bottom of the ranks. The Honda/Acura theme was great as well. I think if GT4 menus had a mix of melodic jazz and hardcore trance, the music would be cool. I go to Gran Turismo 2 to remind me of how far it's come from GT1. As you may know, I consider GT2 the worst one so far because of so many ideas scattered about and actually being SLOWER than GT1. But the cars and tracks combined are enough for any speed freak to come back to GT2. The rally experience wasn't as exciting even though it had my favorite rally track in my favorite style- Smokey Mountain North. GT3 paved the front stretch, and I kind of hated that. Then comes GT3. GT3 is the combination of lessons learned from GTs 1 and 2, just made more beautiful and more challenging. But I sometimes play GT3 anymore. But for any GT fan, play the past two first, then GT3 to appreciate where GT4 is going. Then wait for the PS3 and play GTs 1-4 on your PS2 in anticipation for GT5.