Still to be done are the DMTMP bit, AoE support, possible interface to a venti store, and porting the upper part of the fs kernel to a cpu kernel.
Note too that this kernel can be built as a 32-bit fs kernel, for compatibility with existing on-disk file systems. Thus one could use it just to pick up the other improvements.
N.B.: This kernel has been folded into /sys/src/fs in the main distribution (17 Feb 2006), and is no longer available here.