In this paper, we use the theory of deformation quantization to understand Connes'
and Moscovici's results \cite{cm:deformation}. We use Fedosov's method of deformation
quantization of symplectic manifolds to reconstruct Zagier's deformation
\cite{z:deformation} of modular forms, and relate this deformation to the Weyl-Moyal
product. We also show that the projective structure introduced by Connes and Moscovici is
equivalent to the existence of certain geometric data in the case of foliation groupoids.
Using the methods developed by the second author \cite{t1:def-gpd}, we reconstruct a
universal deformation formula of the Hopf algebra $\calh_1$ associated to codimension one
foliations. In the end, we prove that the first Rankin-Cohen bracket $RC_1$ defines a
noncommutative Poisson structure for an arbitrary $\calh_1$ action.