That hasn't worked for any of my third party apps that are in the app store (TextWrangler, PCalc, Mariner Paperless, ...). I don't have current versions of iLife/iWork so I don't expect them to show up.
If it's listed as "installed" does it somehow show in your "purchases" tab?
B
For instance I already had Caffeine installed and it correctly stated it as 'installed' but it correctly doesn't list it under my purchases.