Codes have been very scarce this time, and they didn't do a giveaway at the forums, which I can understand given how things were on past forum giveaways, with the forum crashing and all the people bashing and complaining.
I have been extremely unlucky with Forza 4, I haven't managed to get a single code for it, neither in the forum giveaways, GWD's, track days, random facebook giveaways, etc... I had to buy every pack, yet I know of people who have managed to get almost all DLC for free, kinda unfair, they should track the winners to make sure these things don't happen. Hell, I haven't even won a unicorn by commenting on RVM's, HMA's, photo competitions, or the monthly rivals event for the M3 GTR. All the unicorns I won have been on the T10 CBH's...
Not that I want to sound like a whiner, but sometimes I feel like I really have bad luck while some other people manage to get DLC's for free, lots of unicorns (even bloating about how they have all 20 and lots of repeats)... At least I had some luck in FM3 and I won a couple of codes.