As some core openMSX developers felt uncomfortable at SourceForge.net because of the story where SF repacked GIMP to include ads, the development team decided to move from SF to Github, at https://github.com/openMSX/. Also the project has a new official address http://openmsx.org.
The change really only affects developers that like to either contribute to the project, or simply check the source code to learn new things.
Link: OpenMSX.org