Google announced that the Android 1.5 NDK Release 1 is available. No, this isn't another SDK. Instead, it's the Native Development Toolkit, which basically allows developers to use C or C++ for development -- with a whole bunch of limitations.
The gist of the goal of the NDK is to provide a way for CPU-intensive operations to be implemented outside of the Dalvik virtual machine to increase performance. The libraries available are limited and it's not designed to allow development of entire applications using native code.
Read more about it at the Android Developer site.