I've just tagged and uploaded sbcl-1.0.41, whose release notes are
changes in sbcl-1.0.41 relative to sbcl-1.0.40:
* optimization: validity of observed keyword initargs to MAKE-INSTANCE is
cached, leading to many fewer expensive calls to
* optimization: in the (unoptimized) general method for MAKE-INSTANCE on a
CLASS argument, search for and call an appropriate optimized ctor function
if it exists.
* bug fix: WRITE always returns the correct value.