For french people or others willing to speak french (and mostly work in france) a well-known site is http://georezo.net/forum/viewforum.php?id=10. Sorry for others! ;-)

The *Georezo* is a non profit organization of volunteers which aims to provide support and gather resources from and for the *french GIS small world*. It provides community tools like bibliography, forums, blogs, ... and gather job ads from private companies and government/public sector.