I'll try to answer everything:
1.- Prizes are given to you at random on many events, just like a jackpot, prizes start turning fast, then slowly, and you get your prize, they are like 20% more xp, or 50% more affinity points, or 4000 cr more, etc.
2.- The M5 Autovista dlc says: "This content is exclusive and is not available for download now". Whatever that means...
3.- You cannot paint exhausts, just the same, body, hood, wing, rims and tint windows options as before.
4.- No local leaderboards.
5.- The most expensive Ferrari is 10 million now (250 GTO).
6.- I imported from FM3 my file, I was level 50, all the cars in the game except unicorns, and DID NOT get the HKS Evo, got like 15 cars and a list was scrolling down saying: You were level50, you get these... You were vip, you get these... You got these rare cars in FM3 garage's you get these..., etc, but no HKS Evo!? But got the unicorn hunting achievement for those "rare cars"...
7.- 11 gigs for FM4 full install (both DVD's) including all DLC from LCE (LCE goodies, plus launch pack, plus track pack which was described as "Top Gear Soccer Field pack and Benchmark Track"?!?! was like 500 megs)
Thanks Tigers Claw
You'll be playing in 24 hours too man, not much time left to wait...
8.- If your wheel doesn't have an analogue stick, you're out of luck, no left right view whatsoever, no way to get inside the cars on autovista or look around the cockpit either... BOOM, thanks T10!! Even if you plug in a controller on the second slot guys!! The game won't let you do those things, you HAVE to unplug your wheel, restart the game with a controller only!!!
Kinect forced on us... No way... I'd rather restart with my controller, I'm not buying a kinect just for that.
Oh, forgot about that badge thing. It is pretty silly IMO, you just get annoying messages pretty often saying: "New badge acquired", all it is is just a little description to change in your in game card which can have different unlockable avatars, your gamertag and a "badge" which are given to you based on your performance on every turn, pass, drift, slipstream, etc... they say e.g. "Clean Passer", "The overtaker", "Bringing home the bacon", etc...
Hope I answered everything!