They've introduced a new "upload its onto Youtube" feature, so you can edit and upload your runs directly from within the game and check it out on youtube.
What's quite prominent in the game now is the whole Gymkhana event ... which is basically Ken Block's baby. You do stunt driving around obstacles in a park. It's quite intense and very addictive!
I thought the driving in Dirt3 was a little hard, but I turned off all assists after a few rounds when I got back into the game and it's been keeping me busy AAAALL weekend! Luckily it still has a ton of classic rally driving which is my favourite - and you can do those races with 60s/70s/80s and 90s rally cars!
But I say again ... 2 player splitscreen is finally here!