We show that any $(\C ^*)^n$-invariant stably complex structure on a
topological toric manifold of dimension $2n$ is integrable. We also show that
such a manifold is weakly $(\C ^*)^n$-equivariantly isomorphic to a toric
manifold.
A Bott tower is an iterated $\CP ^1$-bundle over a point, where each $\CP
^1$-bundle is the projectivization of a rank $2$ decomposable complex vector
bundle. For a Bott tower, the filtered cohomology is naturally defined. We show
that isomorphism classes of Bott towers are distinguished by their filtered
cohomology rings. We even show that any filtered cohomology ring isomorphism
between two Bott towers is induced by an isomorphism of the Bott towers.
A real Bott manifold is the total space of an iterated $\RP ^1$-bundles over
a point, where each $\RP^1$-bundle is the projectivization of a Whitney sum of
two real line bundles. In this paper, we characterize real Bott manifolds which
admit a symplectic form. In particular, it turns out that a real Bott manifold
admits a symplectic form if and only if it is cohomologically symplectic. In
this case, it admits even a K\"{a}hler structure. We also prove that any
symplectic cohomology class of a real Bott manifolds can be represented by a
symplectic form.