luke83, if there won't be any chances to keep surface groups (tags), we dont need this format. Any mesh editor which can handle obj import/export will be fine with that. Obj format does have grouping, but i havent found nice obj editor which will keep these groups.
And anyway, editing polys near meridian_zero (greenwich) will be quite a pain, and there's no format which can ease this.
Unless we start to export and import globe as projected 3d sphere, not 2d map, and unproject it into world.dat.