Of course I run gentoo and I like it to stick to the latest (masked) Gnome version. As it is quite a task to control every package prior to adding it to package.keywords, I worte upgrade_all.

‘upgrade_all’ walks through ‘world’ and finds all packages that would be downgraded on next emerge, shows the according eix-stanza and prompts before adding a stablilizing line to package.keywords. Though it’s a quick shot it works for me, so feel free to edit and extend it, but don’t forget to let me know.