Does OpenOffice.org 2 support OpenType fonts named with “.TTF” (having TrueType outlines?
Yes, to the extent that they resemble TrueType fonts (see below). This may be enough for many users. Part of the value the OpenType format adds is that it allows fonts with better typographic controls, which can support some languages (like Indic languages or Arabic) that other formats don’t support. OpenOffice 2 doesn’t go very far in this direction. See Bug #16032 “OOo should support optional OpenType features” and Bug #78749 “some Latin text needs CTL processing” for more information.