Updated verisons of the CUDA C Programming Guide (v3.1.1) and the Fermi Tuning Guide (v1.2) are now available. You can download them from http://developer.nvidia.com/object/gpucomputing.html.
Notable changes to these guides from the previous versions:
Removed sections about loading 32-bit device code from 64-bit host code using the driver API, as this capability will no longer be supported in the next CUDA toolkit release.
Removed the reference to the canMapHostMemory property and mentioned that all devices of compute capability greater than 1.0 now support mapped page-locked host memory.
Mentioned that host device memory copies of a memory block of 64 KB or less are asynchronous.
Fixed the maximum size of a 3D texture reference for devices of compute capability 2.0 (2048 instead of 4096).
Updated the paragraph about __fdividef(x,y) to clarify behavior depending on compute capability and compilation flag.