Some interesting points about these bindings:

* provides an OO interface to Cairo, using Python 2.2 new style classes.

* treat cairo.Matrix objects as immutable.  The wrappers for things like
cairo_matrix_invert() return a new object, leaving the existing matrix
unchanged.

* cairo_status() is called to check the status of cairo_t operations, and
raise exceptions as appropriate.

* Can be used as a base for other Python extensions.  Will be important when
wrapping other libraries that depend on cairo

* Includes a simple extension with functions for creating cairo.Surface
objects from GdkWindows or GdkPixbufs.  This makes it possible to use the
bindings with PyGTK.
