3d mesh should be implemented in post 1.0 builds.
just imagine david's wolfenstein engine with 3d elements, or 2d games using 3d elements like some XBLA games.
3d mesh support would be extremely useful, and just because things are being shown with 3d meshes doesnt mean they arent in a 2d gamefield. a 3d one can also be achieved as well tho.
we are using direct X, and HWA so 3d support can be implemented. i even believe mmf2 has extensions capable of meshes.
mode 7 effects would also be a nice addition, since its near impossible to do yourself without scanline control(hey, i had trouble trying to do it :'()