Comment 20 for bug 801464

@russianwatcher, @Davide: Can you confirm that this issue still exists with the latest updates? You can use the 'recovery console' session option to do updates if you cannot get into GNOME. I still have not been able to replicate this issue.

Be aware that if you have any shell extensions installed and the GNOME shell is updated, crashes WILL occur. Shell extensions will only work with the shell version that they were compiled on; they will almost always crash the shell if a different version is used.
To remove any shell extensions, run the following command in the 'recovery console' session:
rm -r .local/share/gnome-shell/extensions/*

Everyone affected by this issue, please run the updates and commands specified above (even if you do not think you have extensions installed) and report the results.