paragraph in README re direct-tagging

README.txt

@@ -2,7 +2,7 @@ django-taggit
 =============
 
 ``django-taggit`` a simpler approach to tagging with Django.  Add it to your
-``INSTALLED_APPS`` then just add a TaggableManager to your model and go:
+``INSTALLED_APPS`` then just add a TaggableManager to your model and go::
 
     from django.db import models
 
@@ -14,7 +14,7 @@ django-taggit
         tags = TaggableManager()
 
 
-Then you can use the API like so:
+Then you can use the API like so::
 
     >>> apple = Food.objects.create(name="apple")
     >>> apple.tags.add("red", "green", "delicious")
@@ -26,7 +26,30 @@ Then you can use the API like so:
     >>> Food.objects.filter(tags__in=["red"])
     [<Food: apple>, <Food: cherry>]
 
-
 Tags will show up for you automatically in forms and the admin.
 
+If you don't like the inefficiency of generic foreign keys, and you
+know in advance which models in your project will be tagged,
+django-taggit also supports tagging with direct foreign keys. You must
+create your own intermediary model, a subclass of
+``taggit.models.TaggedItemBase`` with a foreign key to your content
+model named ``content_object``, and then pass this intermediary model
+as the ``through`` argument of ``TaggableManager``::
+
+    from django.db import models
+
+    from taggit.managers import TaggableManager
+    from taggit.models import TaggedItemBase
+    
+    class TaggedFood(TaggedItemBase):
+        content_object = models.ForeignKey('Food')
+    
+    class Food(models.Model):
+        # ... fields here
+
+        tags = TaggableManager(through=TaggedFood)
+
+Once this is done, the API works identically with direct-tagged or
+GFK-tagged models.
+
 ``django-taggit`` requires Django 1.1 or greater.