I'm actually super excited about this. The only thing I don't understand is how they're going to have races with cars and bikes. Even mid-level bikes should be able to obliterate the acceleration and top speed of even high-level cars.
Speed and acceleration.. yes. Handling? No. Get on a track with a few extremely sharp turns. 90 degrees, U turns, that kind of stuff. See how far ahead the cars finish. Your point remains though, in that cars and bikes will never be equivalent. It will be entirely track dependent and I don't see how they make it fair without basing victory entirely on Kudos and not on.. you know, winning.
I'm still going to get the game, but I'm gonna get really annoyed if during the singleplayer game there's races where you essentially have to use a bike to win because the track is more fitting to a bike than a car. I believe they've stated at no point during the game will anyone be forced to use a bike but that doesn't eliminate my.. uh, hesitation I guess.
As someone who really loves PGR3 (100% Gold baby!) I'm a tad worried about all the changes they're making.