Upgrading to Ubuntu 12.04
Ubuntu systems at Google are upgraded every LTS release. The entire process of upgrading can take as much as 4 months and it is also quite expensive as one reboot or a small change can cost them as much as 1 million dollars.
This time, however, Ubuntu 10.04 LTS workstations at Google won't be upgraded to Precise until next year.
Google employees love to use KDE systems and they will be really happy when their systems are upgraded to Precise as lots of great work has been done on KDE since Lucid was released. However, not many employees like new UI changes meant for consumers and not developers. Some of the Google employees also requested removing Unity and Gnome 3 and using xmonad instead.
Lastly he said that 2 years for an LTS release is quite reasonable and gives them enough time prepare things.