I have the same problem as many in the thread. Dmitry posted a script as a workaround. The problem with Skype involves the nvidia driver, so if you’re using the open source graphics driver you shouldn’t be experiencing this.
The script loads mesa driver to be used by Skype.
If you want to solve this problem for all users, then change permission for /usr/bin/skype.
$ chmod 0755 /usr/bin/skype