We have just released preview 3 of Pixel Bender 3D (PB3D) http://labs.adobe.com/technologies/pixelbender3d. This is the best preview to date in terms of reliability and stability. Please look at the release notes (http://labs.adobe.com/technologies/pixelbender3d/releasenotes.html) for the details.
PB3D remains an experiment, where we are exploring the utility of the language for high-level authoring of Stage 3D shaders. Workflows remain command-line based, and it is still easy to write programs that exceed the limitations of Stage 3D. To spend the resources to address the workflow issue would require a significant investment from Adobe, and to justify that we would need extraordinary uptake from the developer community. Please regard the current state of the system as an opportunity to evaluate whether the language is a useful design for your needs, and let us know if you would adopt it for main-line use given a more convenient workflow or language changes, or if it is useful in its current form. Unless PB3D gains significant momentum in the next few months, this is likely to be the last release.
Please note that this announcement only concerns Pixel Bender 3D. Pixel Bender 2D and Flash Player Stage 3D remain unchanged.