Bethesda just announced that they will be releasing the third DLC Old World Blues for Fallout: New Vegas.
Old World Blues will be released on July 19th and will be available for Xbox 360, PlayStation 3, and PC.
Prior to release, we will release a new title update for New Vegas. Along with adding support for Old World Blues, the update will bring improvements to performance and stability in major areas.
There should be one more DLC coming for Fallout: New Vegas after Old World Blues.