Royal Fonts
The Apple "Royal" font format uses a somewhat simpler mathematical description
of character shapes (quadratics) than PostScript's Bezier equations. This
requires more control points to produce the sorts of continuously varying
curves that make up real characters, but Apple claims that the simpler
computation of their font format will result in a lessened computational
burden.
When Apple first announced "Royal" (before Microsoft signed on), Adobe promised
to offer the ability to render Royal fonts on PostScript printers–either by
converting Royal fonts to PostScript format or by providing code to rasterize
Royal fonts directly. Nothing has changed in this promise, so far as I know.
Adobe never promised to offer a tool to convert PostScript fonts into Royal
form, nor to offer Royal fonts.
As of the original Apple announcement, the Royal font rasterizing (the entire
page rasterizing, in fact) was to be done in the Macintosh rather than in a
printer's RIP. Presumably if Adobe offers the promised conversion tool it will
be possible to image Royal fonts on an Adobe PostScript printer; it is likely
that an Apple/Microsoft PostScript clone printer (using the Bauer interpreter)
will be able to rasterize Royal fonts directly.
If one is seriously interested in type and in the advantages of PostScript
(flexibility, availability of a variety of output resolutions and formats,
multiple competing vendors, font library size and quality, and many others), I
believe that it will be possible–indeed desirable–to remain within the Adobe
PostScript orbit on Macintosh, DOS, or OS/2 platforms rather than shifting over
to the Royal font format. I think that PostScript will continue to be the best
choice for serious, quality-oriented users.