So to implement SyncTeX in Gnome, together with Carlos Garcia Campos we added SyncTeX support to evince and exported a new DBUS API so editors can communicate with Evince. Next, I added a "synctex" plugin for gedit, to use the DBUS API exported by Evince. We support both Backward Search (Evince to Gedit synchronization) and Forward Search (Gedit to Evince synchronization).
We also added a new modeline parser, so if you add a complex project with several TeX files you can put
% mainfile: mainfile.texeither in the first or last three lines of each included TeX file, and ForwardSearch will just work (BackwardSearch should always work, even if you don't add the modeline).