Here's hoping it build off of PGR3 the way PGR2 built off of PGR1.
PGR2 was the best in the series so far in terms of the massive amount of (and variety of) cars available, not to mention the massive amount of tracks and of course the boost in graphics.
I understand why PGR3 cut back the number of cars from PGR2 but I really enjoyed the variety available in PGR2, maybe this time they'll bring back the different car types like SUVs, Classic American muscle, economy etc...
I don't think the PGR series really poses much of a threat to GTV, that's really more Forza 2's job... PGR3 concentrates on driving technique and racing through city streets. Forza and GT are more along the lines of realistic car modifications and racing on tracks. PGR caters to the Driving enthusiast while Forza and GT cater to the Racing enthusiest...