Have you ever used OS X? Application state can be preserved and restored across reboots. Most apps do this automatically. Actually I haven't encountered one that doesn't.
- My nested screen sessions with a ton of shells doing things all over the place don't get restored on reboot - My emacs state doesn't get restored on reboot - Chrome reloads all the pages from the network instead of just serializing its entire state and restoring it on reboot
(All of the above are true on linux too.)
Waking the machine from sleep takes seconds; rebooting with stored state takes minutes.
Still, not having to open all the terminals I use for different things and resize and position them is a win. It's the small things. :)
Application state for all three GUI apps I use is pretty much restored on every platform. Thing is, there are only three of them.