bedazzled@bedazzled ~ $ emerge -DuvpNt world|grep -5 gst

These are the packages that I would merge, in reverse order:

Calculating world dependencies  .. ...done!
[nomerge      ] gnome-extra/gnome-media-2.10.2  -debug -ipv6 +mad +oggvorbis
[ebuild  N    ]  media-plugins/gst-plugins-cdparanoia-0.8.10  0 kB
[ebuild  N    ]  media-plugins/gst-plugins-mad-0.8.10  0 kB
[ebuild  N    ]   media-libs/libid3tag-0.15.1b  -debug 0 kB
[ebuild  N    ]  media-plugins/gst-plugins-ogg-0.8.10  0 kB
[ebuild  N    ] media-plugins/gst-plugins-esd-0.8.10  0 kB
[ebuild  N    ] media-plugins/gst-plugins-alsa-0.8.10  0 kB
[ebuild  N    ]  media-plugins/gst-plugins-vorbis-0.8.10  0 kB
[ebuild  N    ]   media-libs/gst-plugins-0.8.10  +alsa -debug +esd -oss 0 kB
[ebuild  N    ]    media-libs/gstreamer-0.8.10  -debug +doc 0 kB
[nomerge      ] gnome-base/gnome-light-2.10
[ebuild   R   ]  gnome-extra/yelp-2.10.0  -debug -firefox* 0 kB
[ebuild  N    ]   www-client/mozilla-1.7.12-r2  +crypt -debug +gnome -ipv6 -java +ldap -mozcalendar -mozdevelop -moznocompose -moznoirc -moznomail -moznoxft -mozsvg -postgres +ssl +truetype -xinerama +xprint 30,307 kB

Total size of downloads: 30,307 kB