We discussed the accidentally-included message argument on line 76 of
the diff in IRC.

I would add failure messages to the asserts inside your custom assert
methods: assertOldLinkMissing, assertOldLinkPresent,
assertNewLinksMissing, assertNewLinksPresent.

Skipping DistroView.setUp on line 345 of the diff and calling
BrowserTestCase.setUp instead confused me.  If I replace it with a call
to DistroView.setUp the tests still pass.

Also, you didn't start it, but the manual test suite construction in
test_suite is kinda ugly and brittle (a test could easily be dropped
from the list and not noticed).  Here's a change that uses the standard
unittest test loader but ignores test cases from the base class that we
want to avoid (also available at http://pastebin.ubuntu.com/593155/).

=== modified file 'lib/lp/registry/browser/tests/test_subscription_links.py'
--- lib/lp/registry/browser/tests/test_subscription_links.py    2011-04-12 14:49:43 +0000
+++ lib/lp/registry/browser/tests/test_subscription_links.py    2011-04-12 14:49:49 +0000
@@ -855,40 +855,19 @@
         self.assertNewLinksMissing()
 
 
+class CustomTestLoader(unittest.TestLoader):
+    """A test loader that avoids running tests from a base class."""
+
+    def getTestCaseNames(self, testCaseClass):
+        # If we're asked about which tests to run for _TestStructSubs, reply
+        # with an empty list.
+        if testCaseClass is _TestStructSubs:
+            return []
+        else:
+            return super(CustomTestLoader, self).getTestCaseNames(
+                testCaseClass)
+
+
 def test_suite():
     """Return the `IStructuralSubscriptionTarget` TestSuite."""
-
-    # Manually construct the test suite to avoid having tests from the base
-    # class _TestStructSubs run.
-    suite = unittest.TestSuite()
-    suite.addTest(unittest.makeSuite(ProductView))
-    suite.addTest(unittest.makeSuite(ProductBugs))
-    suite.addTest(unittest.makeSuite(ProductSeriesView))
-    suite.addTest(unittest.makeSuite(ProductSeriesBugs))
-    suite.addTest(unittest.makeSuite(ProjectGroupView))
-    suite.addTest(unittest.makeSuite(ProjectGroupBugs))
-    suite.addTest(unittest.makeSuite(DistributionSourcePackageView))
-    suite.addTest(unittest.makeSuite(DistributionSourcePackageBugs))
-    suite.addTest(unittest.makeSuite(DistroView))
-    suite.addTest(unittest.makeSuite(DistroBugs))
-    suite.addTest(unittest.makeSuite(DistroMilestoneView))
-    suite.addTest(unittest.makeSuite(ProductMilestoneView))
-    suite.addTest(unittest.makeSuite(ProductSeriesMilestoneView))
-
-    suite.addTest(unittest.makeSuite(ProductDoesNotUseLPView))
-    suite.addTest(unittest.makeSuite(ProductDoesNotUseLPBugs))
-    suite.addTest(unittest.makeSuite(ProductSeriesDoesNotUseLPView))
-    suite.addTest(unittest.makeSuite(ProductSeriesDoesNotUseLPBugs))
-    suite.addTest(unittest.makeSuite(ProjectGroupDoesNotUseLPView))
-    suite.addTest(unittest.makeSuite(ProjectGroupDoesNotUseLPBugs))
-    suite.addTest(unittest.makeSuite(
-        DistributionSourcePackageDoesNotUseLPView))
-    suite.addTest(unittest.makeSuite(
-        DistributionSourcePackageDoesNotUseLPBugs))
-    suite.addTest(unittest.makeSuite(DistroDoesNotUseLPView))
-    suite.addTest(unittest.makeSuite(DistroDoesNotUseLPBugs))
-    suite.addTest(unittest.makeSuite(
-        DistroMilestoneDoesNotUseLPView))
-    suite.addTest(unittest.makeSuite(ProductMilestoneDoesNotUseLPView))
-
-    return suite
+    return CustomTestLoader().loadTestsFromName(__name__)