Yesterday I released Maps and Semantic Maps 0.5.4. This is a minor update which mainly brings additional stability and security to the 0.5.x branch. It contains several bug fixes, a few code improvements and some security fixes. Check out the Maps change log and Semantic Maps change log.
The only new functionality is that you can now define OpenLayers layers in your LocalSettings file, as well as layer groups. This is done by modifying the $egMapsOLAvailableLayers, $egMapsOLLayerGroups and $egMapsOLLayerDependencies arrays, which are defined in Maps_Settings.php.
Another noteworthy point is that Semantic Maps now contains all the geographical coordinate format handling that was part of Semantic MediaWiki earlier on. The code has been removed from SMW itself, and the SMW 1.5 release will be the first one without it. A nice side effect of this is that people still using Semantic Google Maps (one of the extensions Maps and Semantic Maps are based on, which is now obsolete (and really should not be used any more!)) will be forced to switch over to Maps and SM if they want to get the latest SMW.
Both extensions now use Validator 0.2.2, which is a minor update to 0.2.1, which was used in 0.5.3.