From 0.55.0.0 onwards, you can now label menu dividers. You can see an examples of this in the Editor Focus menu, which has both a title (in black) and two labelled dividers (dark grey).
To create these, simply add a label to your item when setting "divider" : True:
menu.append( "/Follow Divider",
{ "divider" : True, "label" : "Follow" }
)