I can attest to the 60 fps. While I haven't played Forza 5, I did play Killer instinct running at 60 fps and videos don't do the game justice. Current videos are only at 30 fps, don't capture the true fluidity of the frame rate.
In that video, I'm noticing differences in the way the environment is scaled in Forza 5, along with the physics (cloth on the banners) and the lighting with the sun.
I hope so. Some of the guys from the MSR/PGR series joined their studio. Next to Wipeout, that's my favorite racing franchise of all time. And now, with no announced Wipeout or PGR, I have to cross my fingers for Driveclub.