Hi,
At last weeks SVG Working Group meeting it was resolved that meshes be accepted as part of SVG 2.0. It was decided that meshes should be treated as geometric primitives if defined outside a <defs> section and as a paint server if defined inside.
I've put my code into a branch that can be obtained at:
bzr branch lp:~tavmjong-free/inkscape/mesh
It must be linked against Cairo trunk.
I've made a few changes since the SVG WG meeting. The attribute 'stop-path' has been rename 'path' at the WG's request. The code now handles 'stop-opacity'. There are five example SVG files in the share/examples directory (their names all begin with "mesh") including one that shows the effect of setting an opacity of less that 1 on two corners of a patch. The examples can also be seen at:
http://tavmjong.free.fr/SVG/MESH/Mesh_Inkscape.html
Note that there is no ability to edit the meshes, it only handles meshes used as gradients, and that there are frequent crashes (possibly in the cairo code).
Tav