  In the context of recently proposed holographic dualities between higher spin
theories in AdS3 and 1+1-dimensional CFTs with W-symmetry algebras, we revisit
the definition of higher spin black hole thermodynamics and the dictionary
between bulk fields and dual CFT operators. We build a canonical formalism
based on three ingredients: a gauge-invariant definition of conserved charges
and chemical potentials in the presence of higher spin black holes, a canonical
definition of entropy in the bulk, and a bulk-to-boundary dictionary aligned
with the asymptotic symmetry algebra. We show that our canonical formalism
shares the same formal structure as the so-called holomorphic formalism, but
differs in the definition of charges and chemical potentials and in the
bulk-to-boundary dictionary. Most importantly, we show that it admits a
consistent CFT interpretation. We discuss the spin-2 and spin-3 cases in detail
and generalize our construction to theories based on the hs[\lambda] algebra,
and on the sl(N,R) algebra for any choice of sl(2,R) embedding.
