Blender 2.48 includes all the work done on the Blender Game Engine and the Apricot Open Game "Yo Frankie!", with much better functioning game logic editing, character animation, and Blender Material based real-time shaders. And as last minute surprise a Bullet physics update with Softbody support.
Also in this release; Windows 64 bits support, Grease Pencil for sketching annotations, Sun/Sky/Atmosphere rendering, new modifiers, and an improved text editor with Python API support. And last but not least, an enormous list of open bug reports were handled.
Blender 2.48a update:
A couple of important bugfixes has been done in Blender since the release, especially for using the Game Engine and GLSL. Read more here.
You can get many of Blender's Materials also drawing in real-time in the 3D window and the game engine, including shadow buffers! It requires a more recent 3D card with good hardware shader support.
Game logic and game level editing has been improved in many ways. Most notable are the Logic States, which allow to group logic bricks in simple"state engines" and activatate, deactivate, or smoothly make transitions between them.
Blender's GE uses the Bullet physics library. The library has been updated to the latest version, supporting soft body dynamics. Support has been added for flat cloth or volumetric soft bodies. Bullet allows interactions beween soft bodies as well as rigid bodies and static collision bounds of all types.
The Game Engine is back, and better than ever! In this section you can read some of the backgrounds, and a collection of other GE release notes.
You can assign an RGB color to any lamp's shadow now. Although this isn't a feature supported "in the real world", it's a cool trick to allow artists to present a more realistic shading and lighting in their work (without need for GI).
As one of the Google summer projects, you can now allow an object to be "shrinked" to match/touch another object's shape. The modifier works based on vertex groups allowing a part of a model to shrink or be projected
This new modifier has been added to provide simple deforms. It works on Meshes and Curve objects, and provides twist, bend, taper and stretch.
The Grease Pencil allows to sketch annotations, notes and even animated motion suggestions in Blender. Great for collaborated work, remarks from directors or to draw key frame poses for characters.
A lot of work has been done on better management for inserting keys. Further you can read notes here about rigging, bone locking and aligning. And there's a Mancandy reference rig update!
This new "sun/sky" feature allows to use Sun lamps to simulate sky color and atmosphere scattering. A lot of options are available to achieve interesting artistic results, including blend modes and color space.
A couple of new Sculpting options were added. Now brushes allow a custom falloff curve, and there are more options available for textured brushes.
One of the included Google summer projects was to improve our texteditor with Python IDE features, allowing much more advanced editing and integrated API lookup support for scripters.
Fluid simulation can be controlled using particles which define local force fields and are generated automatically from either a physical simulation or a sequence of target shapes. At the same time, as much as possible of the natural fluid motion is preserved.