This year Jay Sean will headline the big event on April 28 and I have to admit his hit song "Down" is damn catchy. Other performers will include Flogging Molly, Rooney and Big D & the Kids Table. There will be daytime sets too, but those haven't been announced yet.
The event is not technically open to the public, but the event is held in the very open main quad near the Bryan Center on Duke's west campus. In past years, I've never been asked for an ID. Here's the official policy.
Students are required to carry their DukeCards with them at all times and may be asked to present it to demonstrated they are a Duke student. Due to safety concerns, the event is not open to the public. Non-Duke affiliates (excludes faculty and staff) will not be allowed on campus.So essentially, if you don't do anything stupid to draw attention to yourself, you should be fine, but you've been warned.
Check out a few photos and a review of Ben Folds' LDOC set at Duke last year here.