The Half-Life 2: Wars team have just released a large update to their Half-Life themed RTS modification, version 0.5. According to their website, the release features "new maps, upgraded AI, and basebuilding for both Resistance and Combine, [and] a whole host of upgrades to the game, such as unit sounds, balance and gameplay tweaks, better visuals, and a lot of other small improvements." The following screenshots are from the release:

Short Changelog:
* Two new maps
* Changed to Orange box engine
* Added basebuilding
* Improved stability
* Improved units AI
* Added support for navigation mesh
* Improved balance between units
* Improved various visuals

The release requires Orange Box to play, and earlier versions of HL2:Wars must be removed prior to installation. Download the EXE or ZIP version of the install files, and visit their website or forums for more information.