python-updater can take a really long time to figure out which PMS command to run (45 minutes here for a python-2.4 -> 2.5 upgrade), only to have the invoked emerge (or whatever) command fail due to some reason or another (intentionally-masked packages, specific ebuild versions no longer being in the tree, &c.). Like revdep-rebuild, it should echo the pms command so the user can just re-execute it with changes if need be.
Created attachment 161303 [details, diff] diff to echo the command
Please update the summary with what version of python-updater you are using.
This is in svn¹ and will be released with the new version soon. ¹: http://overlays.gentoo.org/proj/python/changeset/109
Version 0.6 should fix this, thanks for reporting.