The Blender Foundation announced Blender 2.65 recently saying stability had been their main focus this cycle. This release represents over 200 bug fixes and several new features.
One of the new features is the addition of fire to the smoke simulator, which received lots of updates and performance improvements. "Smoke can be emitted from mesh surfaces, without the need for a particle system. A smoke flow force field was added to improve interaction with other simulations. Colored smoke simulation and mixing is possible and the interaction of smoke...Read more at OStatic