Speed, speed, speed is the ultimate goal of Ubuntu 10.04 Lucid Lynx release.
Under 10 second booting will be one of the key component in that.
According to "the ubuntu fridge", here is what it says about the release...
"Speed is an essential ingredient in the attack of a lynx, and speed remains our goal. We have improved the boot time in each of the releases during this era of Ubuntu, and expect to complete some of the major improvements required for 10 second booting with Lucid. Fully harnessing Upstart, in collaboration with Debian, will get us even closer to the goal."