I realise you're done with Gentoo, but I just want to make sure people are aware of
ACCEPT_KEYWORDS="~amd64"
which automatically installs "unstable" versions of packages. Unstable is pretty damn stable in my experience. Maybe not server-proof, but fine for a desktop.
The guideline there is about a month and no outstanding bug reports. That would be perfect, but unfortunately packages lag because it is easier for the maintainer to not mark them stable. It has probably been discussed before, but the inertia being towards things going stable with inaction rather than the other way around would help.