We just released TileMill 0.10.0, the latest version of our open source map design studio. This release redefines the creative possibilities for web cartography with its new support for compositing layers and features, achieving photoshop-like clipping, masking, blurring, or highlighting. This powerful set of compositing operations can be used seamlessly across vector and raster layers all using pure CartoCSS. The compositing now possible in TileMill, in combination with image patterns or raster hillshades, can enable effects of uniqueness and beauty that go beyond was has previously been possible.
Someone needs to create a CartoCSS importer for ArcGIS to free their users from those crazy tabbed cartography preference windows. Actually, I can only imagine the headache to create such a tool, just move to TileMill for your cartography.
This from CSS, just awesome!