I have been running qgis in Mountain Lion for a few weeks now, but when I upgraded to OS X 10.8.1, qgis would no longer work. I get an error saying:
QGIS cannot be opened because of a problem. Check with the developer to makes sure QGIS works with this version of OS X. You may need to reinstall the application. Be sure to install any available updates for the application and OS X.
I have tried re-installing qgis (I have even tried installing the nightly build) and I have also updated all of the packages that qgis requires.
Has anyone had a similar problem or more importantly, does anyone have a solution?