  The Goldstone mode in the ordered phase of itinerant helimagnets, such as
MnSi or FeGe, is determined and shown to have a strongly anisotropic dispersion
relation. The softness of this mode is, in a well-defined sense, in between
that of ferromagnetic and antiferromagnetic magnons, respectively. It is shown
that this soft mode leads to nonanalytic corrections to Fermi-liquid behavior,
with a T-contribution to the specific heat coefficient, and a
T^{5/2}-contribution to the resistivity. The quasi-particle inelastic lifetime
shows anisotropic behavior in momentum space.
