It boots from scratch each time, but still takes less than 10 seconds to start playing music. I've not timed it, but I reckon around 6 or 7 seconds.
It starts playing from within a second of where it turned off in the same track and playlist.
The "east" and "west" buttons on the front of the unit currently (I'm running beta4) allow "skip to next track in current playlist" and "skip to beginning of this track or back to the previous track in this playlist". Through a menu option you can select playlists, currently only backwards and forwards in an unsorted list. I understand that the folks at Empeg are working on much more featureful track/playlist navigation functions, possibly with most of it available only via the remote or via the menus rather than through simple front panel button presses, which is reasonable because there's a limit to how many different ways you can overload 4 buttons.
One thing you can't currently do, and I don't know whether it's planned, is "skip to next/previous inner playlist", which would give you the equivalent of next/previous CD on a conventional CD changer.