Problems in recent Gentoo updates(2010/09-2010/10)

When I updated the entire system fully in gentoo in recent, met lots of problems.
when I run:
emerge --update --deep --newuse world
lots of errors occurred, the following problem .

1.slot conflict
!!! Multiple package instances within a single package slot have been
pulled
!!! into the dependency graph, resulting in a slot conflict:...
Solution: emerge --unmerge all these conflicting packages, and continue.

2.emerge failed for qt-gui-4.6.2
solution: emerge cairo pango gtk+ firstly.
emerge -1 cairo pango gtk+
emerge qt-gui

3.emerge failed for xine-lib-1.1.18.1,
errors say symbols related to XXXoggYYY could not be found.
emerge flac before emerge xine-lib.

4.no sound in smplayer/mplayer, smplayer give error code of 127:
solution: remerge mplayer smplayer:
emerge mplayer smplayer

5.no cursor shown in x windows (if boot into x window directory, for example using xdm & slim), but cursor could move. If switch to console by Ctrl+Alt+F1, then the cursor would come up. it is a bug in xf86-video-intel (such as version ).
Solution:
After rm -rf ~/.cache ~/.config/xfce4
the cursor come back.

6.icon disappeared in xfce menu.
solution:
emerge -av tangerine-icon-theme tango-icon-theme tango-icon-theme-extras