At the end of the sys-devel/icecream emerge (at least in 0.7.14), there is a message which states: * The icecream monitor is no longer included in this package, emerge * kde-misc/icemon if you wish to graphically monitor your compile cluster. However, it doesn't seem as if there is a package called kde-misc/icemon, unless it is somewhere in an overlay.
Good point, it's not in the tree yet because it's unversioned. It's on bug #139432.
Fixed, thanks!