  The nonlinear interaction of waves in a driven medium may lead to wave
turbulence, a state such that energy is transferred from large to small
lengthscales. Here, wave turbulence is observed in experiments on a vibrating
plate. The frequency power spectra of the normal velocity of the plate may be
rescaled on a single curve, with power-law behaviors that are incompatible with
the weak turbulence theory of D{\"u}ring et al. [Phys. Rev. Lett. 97, 025503
(2006)]. Alternative scenarios are suggested to account for this discrepancy --
in particular the occurrence of wave breaking at high frequencies. Finally, the
statistics of velocity increments do not display an intermittent behavior.
