iTunes 11
Interesting play Issue with MiniPlayer
As I mentioned below, I had to fix a script to workaround a problem playing a playlist when only one track had as yet been copied to it, which prevented the rest of the subsequently added tracks from being recognized by MiniPlayer and Up Next; thus, only the first track would play. Similarly, if you were to play (the AppleScript command) any track in a playlist, the following tracks will not play because they haven't been recognized by MiniPlayer and Up Next ("No upcoming songs").
Doesn't go good when Mini Player is empty:
You can play the playlist and everything's OK. You just can't initiate play of the entire playlist by playing one of its tracks with AppleScript.
Goes good and loads in MiniPlayer:
Additionally, I found that if the MiniPlayer was already loaded up with tracks, playing a track (via AppleScript) from anywhere would play that track and then resume with whatever is next in MiniPlayer.
iTunes 11 Loses playlist window
Technically, you can't open a playlist in its own window in iTunes 11, so the playlist window element is moot.
UPDATED: Play Random Album v3.1
Play Random Album scans your library, creates a playlist of a complete single album choosen at random and begins playback of the playlist created. Works great when assigned a keyboard shortcut.
This version works around a problem with iTunes 11 whereby after starting to play the first track of the new playlist no additional tracks appear in the MiniPlayer/Up Next and only the first track ever plays. The script now waits until the playlist is completely assembled before starting to play it.
iTunes 11 Loses Gapless Track Feature
You can no longer designate an album of tracks as gapless. Thus, a track's gapless property is now moot.
ERRATA: My title for this post is misleading. The gapless feature has not been lost. But the ability to manually change a track's gapless setting has been removed.
iTunes 11 Released
Apple has released iTunes 11. Apple originally previewed iTunes 11 at its September Special Event, announced a vague October release date, and then later postponed release to November.
This updated version features some iOS-inspired GUI changes, re-designed MiniPlayer, improved iCloud integration, improved search, and a revamped design of the iTunes Store.