Hi,
you can download the last version of SPIP at
http://files.spip.org/spip/SPIP-v1-9-2.pr2.zip
or with svn :
svn://trac.rezo.net/spip/branches/spip-1.9.2
The list of improvement and bugs corrected since 1.9.2pr1 can be found here :
http://trac.rezo.net/trac/spip/log/branches/spip-1.9.2
enjoy !
.Gilles