Yau's nodal volume conjecture

Let $(M,g)$ be a compact Riemannian manifold without boundary, and let $\varphi$ be an eigenfunction satisfying

$$\Delta\varphi=-\lambda^2\varphi.$$

Write $\mathcal{L}_{\varphi}(M)$ for its nodal volume. Yau's conjecture. There exist constants $c_1(M,g),c_2(M,g)>0$ such that

$$c_1(M,g)\leq \frac{\mathcal{L}_{\varphi}(M)}{\lambda}\leq c_2(M,g).$$

Thus the nodal volume should be of the order of the corresponding frequency. The source provides no evidence that this conjecture has been resolved in the stated generality.