I'm not sure I'd ever try it myself — for one thing, PostScript would only be useful for preparing documents destined for print, not HTML — but if I ever did need such a thing, I'd be interested to try it out.
Whether the rasterization in the end targets a printer or it ends up in a .png doesn't really matter at all.
But yeah, sadly there's no readily available system nowadays with true Display PostScript. Not very likely that Oracle will release the NeWS sources, and OS X switched to DirectPDF.
