This new font handling really bothers me. The built-in fonts cannot display special characters (like hungarian or polish as mentioned before), and the manually added ones appears unreadably thin.
I managed to replace the built-in Georgia to the same type with full character set, so now i have this one and only font to read hungarian texts. Still can't use my favorite one, Gentium Book Basic. (by the way, there was a poll of font preferences...)
I think this "font tuning" is pointless anyway: the limited display resolution and number of grey shades causes that only a handful of size and antialias combination looks acceptable. A competent typographer should choose a wide variety of typefaces and set them look good on this device, instead of let the readers struggle to find a good setting.