Mantaflow is a unified smoke and liquid simulation that might replace the ones in Blender at some point in the future. Currently it is developed in a branch and after two GSoCs, some early results can be shown.
Once again BlenderDIplom tested the new features, in this case liquid simulations. Note that during the time when the tests where done, little more than dropping fluids into fluids was possible. Only recently basic obstacle support was added. But the fluid in general shows a good quality, especially in regards of the stability of liquid sheets: