They will headline the 2002 to Warped Tour along with NOFX and the Mighty Mighty Bosstones. Check out Artistdirect.com for all the info. (thanks to Cody Clements for this info.)
Rumours of Brian leaving Bad Religion are false. He will contribute to the recording of the new Dag Nasty album, due out later on this year, but he assured me he will not tour with Dag Nasty, let alone quit Bad Religion.
The March issue of Spin magazine has a three-page feature on BR (starting on page 90).
Here is a 14-minute online video interview with Brett and Greg discussing The Process Of Belief. And here you can download BR's appearance on Conan O'Brien from a couple of weeks ago. Finally, you can find BR's performance of Sorrow from the Craig Kilborn show here (click on videos on the upper left side, then click on rock; it comes up in the vertical black stripe to the right of videos.)