Fix stupidities:

1) I left a bunch of unused declarations in tag_view.py
2) I needlessly made a copy of user_categories in DB2

src/calibre/gui2/tag_view.py

@@ -200,13 +200,6 @@ class TagTreeItem(object): # {{{
 
 class TagsModel(QAbstractItemModel): # {{{
 
-    categories_orig = [_('Authors'), _('Series'), _('Formats'), _('Publishers'),
-                       _('Ratings'), _('News'), _('Tags')]
-    row_map_orig    = ['authors', 'series', 'formats', 'publishers', 'ratings',
-                       'news', 'tags']
-    search_keys=['search', _('Searches')]
-
-
     def __init__(self, db, parent=None):
         QAbstractItemModel.__init__(self, parent)
 
@@ -257,12 +250,6 @@ class TagsModel(QAbstractItemModel): # {{{
 
         return data
 
-    def get_search_nodes(self, icon):
-        l = []
-        for i in saved_searches.names():
-            l.append(Tag(i, tooltip=saved_searches.lookup(i), icon=icon))
-        return l
-
     def refresh(self):
         data = self.get_node_tree(config['sort_by_popularity']) # get category data
         for i, r in enumerate(self.row_map):

src/calibre/library/database2.py

@@ -743,7 +743,7 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
             categories['formats'].sort(cmp=lambda x,y:cmp(x.name, y.name))
 
         #### Now do the user-defined categories. ####
-        user_categories = dict.copy(prefs['user_categories'])
+        user_categories = prefs['user_categories']
 
         # remove all user categories from tag_browser_categories. They can
         # easily come and go. We will add all the existing ones in below.