  We describe some recent development on the theory of formal Frobenius
manifolds via a construction from differential Gerstenhaber-Batalin-Vilkovisk
(DGBV) algebras and formulate a version of mirror symmetry conjecture: the
extended deformation problems of the complex structure and the Poisson
structure are described by two DGBV algebras; mirror symmetry is interpreted in
term of the invariance of the formal Frobenius manifold structures under
quasi-isomorphism.
