IDEAlliance has posted the call for participation for XML 2008. This year it moves back to the D.C. area (Marriott Crystal Gateway, Arlington, Virginia to be precise) after several years in Boston. I've had a great time at this show for the last couple of years, and it's the major XML event in the U.S. The show runs from December 8-10. I likely won't be able to attend this year, but I do highly recommend it nonetheless.