Main OSM blog (blog.openstreetmap.org)
The main blog.openstreetmap.org blog (http://blog.openstreetmap.org) is a blog with all manner of news about OpenStreetMap.
Although it is one of many Blogs in and around OpenStreetMap, it is the main official blog of OpenStreetMap run by the OpenStreetMap Foundation and specifically the Communication Working Group. Not to be confused with http://blogs.openstreetmap.org , an aggregation of many different unofficial blogs and diary entries from community members.
Contact the Communication Working Group if you would like to contribute to this official blog. We need new blog post authors (whether you have a one-off idea for a particular post or you'd like contribute regularly) and also translators.
blog.openstreetmap.org is actually the new location for several other blogs which were merged together at this location. The main blog used to be called OpenGeoData, and indeed the majority of blog posts in the archive are from this original blog. Quite a few other posts were merged in from the OSM Foundation blog at blog.osmfoundation.org when this new site was set up in May 2013. See OpenGeoData for more on this history.