I suppose a complex application that takes a long time to start in its own right (OpenOffice, I'm looking at you) might take some hints from the methodology and try to parallelize and optimize its startup tasks. I'm not sure how far you get with a userspace app like that though.
I suppose if you have an embedded device that actually gets powered off and on semi-regularly (media player, cell phone), this work directly impacts the user experience. Those devices could actually boot from scratch rather than dumping state to flash for suspend when they power off. That extends flash lifetime, and it makes startup and shutdown quicker.
My current cellphone takes a good 15 seconds to boot. Booting in 5 would be a noticeable improvement. Granted, I only shut it off when I'm flying somewhere or when the battery gets obnoxiously low, but still, it could make you a favorite with the jet setters. Seeing as there's already interesting Linux distributions running on OpenMoko, I'm sure there's plenty of opportunity for cross-pollination. (Check out this one: http://mobile.slashdot.org/article.pl?sid=08/09/21/1730256 )