In Code Listing 2.1 in the GNOME Configuration HOWTO, the following appears: USE="-qt -kde gtk gnome hal howl" The qt USE flag has been replaced by qt3 and qt4. A new user following this guide who doesn't want anything qt-related is going to be unpleasantly surprised.
I also found you need -arts in the USE flag to prevent QT being emerge'd too. I'd suggest replacing in section 2.1: USE="-qt -kde gtk gnome hal howl" with USE="-qt -qt3 -qt4 -kde -arts gtk gnome hal howl"
Good idea. And while we're at it, how about replacing "howl" with "avahi"? Howl is not being developed any more, but avahi is.
Fixed. Thanks for reporting.