diff --git a/django/contrib/staticfiles/management/commands/collectstatic.py b/django/contrib/staticfiles/management/commands/collectstatic.py
index aae6bee10e..daf7ab26f0 100644
--- a/django/contrib/staticfiles/management/commands/collectstatic.py
+++ b/django/contrib/staticfiles/management/commands/collectstatic.py
@@ -39,9 +39,9 @@ class Command(NoArgsCommand):
         if options['use_default_ignore_patterns']:
             ignore_patterns += ['CVS', '.*', '*~']
         ignore_patterns = list(set(ignore_patterns))
-        self.copied_files = []
-        self.symlinked_files = []
-        self.unmodified_files = []
+        self.copied_files = set()
+        self.symlinked_files = set()
+        self.unmodified_files = set()
         self.destination_storage = get_storage_class(settings.STATICFILES_STORAGE)()
 
         try:
@@ -124,14 +124,14 @@ Type 'yes' to continue, or 'no' to cancel: """)
                 # storage doesn't support ``modified_time`` or failed.
                 pass
             else:
-                destination_is_link= os.path.islink(
+                destination_is_link = os.path.islink(
                     self.destination_storage.path(destination))
                 if destination_last_modified == source_last_modified:
                     if (not symlink and not destination_is_link):
                         if verbosity >= 2:
                             self.stdout.write("Skipping '%s' (not modified)\n"
                                               % destination)
-                        self.unmodified_files.append(destination)
+                        self.unmodified_files.add(destination)
                         return False
             if dry_run:
                 if verbosity >= 2:
@@ -157,7 +157,7 @@ Type 'yes' to continue, or 'no' to cancel: """)
                 except OSError:
                     pass
                 os.symlink(source_path, destination_path)
-            self.symlinked_files.append(destination)
+            self.symlinked_files.add(destination)
         else:
             if dry_run:
                 if verbosity >= 1:
@@ -180,5 +180,5 @@ Type 'yes' to continue, or 'no' to cancel: """)
                     if verbosity >= 1:
                         self.stdout.write("Copying %s to %s\n"
                                           % (source_path, destination))
-            self.copied_files.append(destination)
+            self.copied_files.add(destination)
         return True
diff --git a/tests/regressiontests/staticfiles_tests/tests.py b/tests/regressiontests/staticfiles_tests/tests.py
index 6999b7af30..0a6c060664 100644
--- a/tests/regressiontests/staticfiles_tests/tests.py
+++ b/tests/regressiontests/staticfiles_tests/tests.py
@@ -7,12 +7,13 @@ from StringIO import StringIO
 
 from django.test import TestCase
 from django.conf import settings
+from django.contrib.staticfiles import finders, storage
+from django.core.files.storage import default_storage
 from django.core.exceptions import ImproperlyConfigured
 from django.core.management import call_command
 from django.db.models.loading import load_app
 from django.template import Template, Context
 
-from django.contrib.staticfiles import finders, storage
 
 TEST_ROOT = os.path.dirname(__file__)
 
@@ -54,6 +55,11 @@ class StaticFilesTestCase(TestCase):
             "regressiontests.staticfiles_tests",
         ]
 
+        # Clear the cached default_storage out, this is because when it first
+        # gets accessed (by some other test), it evaluates settings.MEDIA_ROOT,
+        # since we're planning on changing that we need to clear out the cache.
+        default_storage._wrapped = None
+
     def tearDown(self):
         settings.DEBUG = self.old_debug
         settings.MEDIA_ROOT = self.old_media_root