Answer
There is no direct conversion or import of ArcInfo workstation symbols for or into ArcMap, nor will you be able to use IGL or PostScript fonts. However, you will be able to use any TrueType fonts and re-create your symbols based on them.
When building new styles, please note that the marker centering is improved. It is now based on the center of the graphic extent of each glyph and not on the overall cell extent for the character box.