Many times when we get notification that updates are available for the system we often click on install update button without even looking at the details as we know keeping the system up-to-date keeps it stable. But many times once updating is finished systems asks for reboot and everytime its not possible to reboot immediately. For example when we are working on remote sessions on telnet or ssh or editing something important on internet.
It may also be observed that untill you do not reboot the system it behaves irratically.

The update-manager is very outdated and it's not integrated with the rest of the system.

Recently we upgraded to 12.04 from 11.10, kubuntu 32 bit. And lost google-earth in the process (OS freezes). There's a bug report on it but its not fixed yet. So to make things a bit easier why not retain a coupla previous kernels within the repositories? That way what worked prior to updates/upgrades will probably work again (if it happens to be a kernel issue like this one).

One may require some type of "Regress" checkbox within the package maintainers (synaptic, muon, whatever)... or a new source list could be implemented to make the prior kernel(s) available.

Of course would not normally regress unless a specific app critical to normal usage went bust from a subsequent kernel update (such as was my (and many others) situation).