The Mozilla Foundation just released another update of the Firefox web browser to version 3.6.8, very shortly after releasing version 3.6.7. There is only one bug fixed though, which has resulted in stability issues. The new version should work as expected again.
Google also released a new version of its Chrome web browser. Version 5.0.375.125 fixes 5 security vulnerabilities, of which 3 are considered highly critical by Google. You can check if you have the latest version running by hitting the settings icon on the top right of Chrome and go to the About-entry.
As web browsers pose the highest risk for getting attacked by cyber criminals, they should be kept up-to-date and therefore the updates should be installed ASAP.