It seems WRI has changed the way fonts are dealt with in Mathematica 9 and 10.
The following command
Export["test.eps", "This is a nice formula"]
in Mathematica 9 (after import to Illustrator)
whereas it yields
in Mathematica 10. In other words, the font it not recognized anymore by Illustrator CS3. This is using Macos X.
I have tried uploading the Mathematica fonts from http://support.wolfram.com/kb/10427 but it does not seem to help.
Any ideas? (My apologies for a possibly silly question)
Following @Szabolcs remark I tried
Export["test.pdf", "This is a nice formula"]
In Mathematica 9 I get a 1.3 Mb (!!) file which works fine in Illustrator
In Mathematica 10 I get
which is hardly progress!