+1 for this, /guildbook open is less obvious, and having something like the following:

/guildbook
/gb (alias for /guildbook)

then maybe hyper specific opens like

/guildbook calendar
/guildbook bank
/guildbook profile
etc

for each of the related tabs to be brought right there. Could be Macro'd functionality into actionbar buttons for customization, or just for people who like typing things.

There are now some keybind options in the standard keybind menu if this helps.

Would still really love a slash command. Lots of people do not want to set a keybind and hide the minimap. If you do that there is no way to use this addon.