Quote from quakecon.org:
We’re less than four months from QuakeCon, and to get ready, we’re opening pre-registration tomorrow!

While general admission to QuakeCon remains FREE for all attendees, when pre-registration opens we will be offering premium packages. These premium packages are limited and will be available on a first-come first-serve basis.

Apparently, they're selling premium packs that include shirts and posters. Also, QuakeCon 2012 will take place on-site at the Hilton Anatole Hotel in Dallas, TX. Doors to QuakeCon will open on Thursday, August 2nd at 9:00am Central and will remain open through August 5th.

QuakeCon remains FREE to general admission and BYOC attendees thanks to the support of id and Bethesda Softworks, as well as the QuakeCon volunteer staff and the 2012 event sponsors and exhibitors.