The RUF's are in! They may not be premium but you will be able to drive a Porsche in that sense in GT5.
Anatoray, there is too much Euro/American cars in it for me
. I hope for more JDM. But they will probably give more US/Euro by DLC I would assume. I don't see GT5 claiming to be anything except a racing simulator. Not sure how that would tie in with Porsche at all. Plenty of races happen by cars that are not Porsche.