There has been interest in the availability of the RenderScript GPU driver for Juno.
I'm pleased to say that the Juno driver is expected to be released by the end of January 2015.
The January release will support 32bit RenderScript bytecode only on the GPU driver. Applications (apk's) containing 64 bit RenderScript bytecode will run on the CPU driver. It's worth noting that an application built for Android SDK version less than 21 will only contain 32bit bytecode anyway.We expect to have 64 bit bytecode support on the GPU driver in February 2015.