A graphical install of Winston Beta-3, even one where you select X/Windows (and GNOME and/or KDE), will reboot to a text-mode login. The initial runlevel defaults to 3, and X won't start until this is changed. If that's the way the software is going to operate, I think this needs to be mentioned at the end of the install process. The way the docs are written now, the last page of the I.G. install process (install-guide- en\s1-install-congrats.html, "Installation Complete") points the user to the G.S.G. It's only when you get to gsg-en\ch-starting.html, partway down the screen, that you have "To change your login screen" with a pointer to the Chapter 17 FAQ. I think this is too late, likely to be missed, and will leave the user wondering what to do at that scary black-and-white login screen. I think the "Installation Complete" page should have the reference to the Chapter 17 FAQ (process for changing runlevels) also.
In our experiences, the installer, when so directed by the user, will appropriately set the runlevel for an X-based graphical login. If you are seeing otherwise, that's an issue for the installer, not one for documentation.