Looks like the biggest (at at least biggest list of features / fixes) to date is out now.  You can download it from the NASA WWJava Page.  Pat Murris has a blog posting with several of the major changes he has noticed.

In brief:

• - Configuration made consistent and independent
• - Configuration defaults moved to usage sites
• - Logging mechanism and semantics cleaned up
• - Shutdown entry point
• - Package refactoring
• - Memory cache refactoring and optimization
• - Reimplementation of Polylines. Polylines on surface.
• - Shapes (but the Surface versions will be superseded in next release)
• - Shape and icon dragging
• - Math classes re-engineering
• - View and input handling changes
• - Examples — see src/gov/nasa/worldwind/examples
  • - Template for WWJ apps
  • - Template for WWJ panels
  • - WMS Manager
  • - Layer manager
• - More general icon image specification
• - WMS capabilities doc parsing
• - WMS layer specification improved
• - WMS Layer Manager
• - Thread-safe icon collections in IconLayer
• - RPF parsing and display
• - Applet example and javascript interface
• - New layers
  • - Country boundaries
  • - USGS Topo
  • - Stars
  • - Fog
  • - Scalebar
  • - World Map
  • - Terrain Profiler
• - Layer panel utility
• - Performance statistics utility
• - Bug fixes
• - Instrumentation and Run-time statistics
• - Texture cache
• - Proxy support
• - Anaglyph stereo