There is one slight difference only with regard to the name table of TrueType and PostScript flavored OpenType fonts. From the OT spec (
http://www.microsoft.com/typography/otspec/name.htm):
Full font name; this should be a combination of strings 1 and 2. Exception: if the font is “Regular” as indicated in string 2, then use only the family name contained in string 1.
An exception to the above definition of Full font name is for Windows platform strings for CFF OpenType fonts: in this case, the Full font name string must be identical to the PostScript FontName in the CFF Name INDEX.Except from that the name tables should be identical.
But if you want to make out those differences in future, don’t ask Microsoft, but decompile the name table of the TT-OT and the PS-OT version of your font with the help of TTX and compare the tables:
http://sourceforge.net/projects/fonttools/