Comment 13 for bug 645896

to reproduce this bug. right click on any folder, select 'open with other application' select any app from there and click 'open' ('remember this application for "folder" files' should be ticked). the app that you selected to open the folder will open. now if you open your home dir or any sub-dir in your home from 'Places' menu the associated app will open.

To solve the problem: right click on any folder, select 'open with other application' a dialog will pop, there select 'file brower' and click open. now everything should be back to normal.