... hopefully.
First at all, I don't think that the flat six engine will die very soon. This is the traditional 911 engine and Porsche would make a huge mistake by completely replacing it with a V8 or anything else. Not a very clever thing to do if you ask me.
The V8 from the Cayenne is a very interesting product and should be ideal to be used in the rumored 4th Porsche model.
I still think that the GT or whatever Porsche will call this thing (funny, I heard the name "980"
) won't make it to the markets before 2006 ... earliest.
I'm even sure that the 4th model will depend a lot from how the Cayenne will sell ... or not.
As far as I heard, no final decision has been taken about a 4th model. This means that ANY talk about the 4th model is PURE speculation right now.
Just relax, buy your 996 Turbo and enjoy it. It doesn't make sense to try to predict what will happen in three years.
Would you be happy if I'd tell you that in three years, the 911 Turbo gets minimum 500 HP? I guess not.
Enjoy what Porsche has to offer today and start worrying about tomorrow when you get bored of it.