Shipped my 12GS down from Los Angeles for the 2011 follow till rest day 7 in Northern Chile and then rode back. Hooked up with a privateer from Wales and his support team. Was way cool the Dakar gets in your blood, cried everyday that I watched this year on TV/Internet. You can find the specials and see the off road stuff on line the day before.
All the cops and people know the viewing spots but you need to speak Spanish!
True the Bivies at night are the spot to be and are impossible to get in with out passes. But the towns and regular folks are partying every night that the race is in town. You ride into town and people surround your bike put the kids on for a photo and generally believe your someone cool from the Dakar:-)
Personally had more fun hanging with the babes in town than the mechanics at the Bivies
There are tons of support groups you can pay/sponsor a bit to hang with. The other way is 20k with lame butt tours.