When a bug listing includes duplicate bug reports (in an advanced search, or in the listings that will appear by default when bug 5977 is fixed), the duplicate reports are not indicated any differently from non-duplicate ones, and there is no link to the report they're a duplicate of.
For example, <https://launchpad.net/~emmajane/+reportedbugs?field.omit_dupes.used=> contains several duplicates, but you can't tell which of them are, or go to the originals, without examining each in turn.
At least six mutually exclusive solutions have been proposed:
Bug 3796 suggests displaying duplicates as "Duplicate".
Bug 28868, bug 38344, and bug 299283 suggest keeping their status in sync with the master report.
Bug 55730 asks for either of the above.
Bug 3785 and bug 66488 suggest marking them as "Rejected" (now "Invalid").
Bug 46113 suggests displaying them as "closed".
And bug 492011 suggests marking them as "Fix Released".
Please excuse the irony, but this is a duplicate. :-)