I used to be able to batch-download songs from iTunes Match on my Mac by selecting a group of tracks and choosing Download from the contextual menu, but that option seems to be missing in iTunes 11 (11.1.3 to be precise). Don't want to have to click several thousand songs individually — is there still a way to batch-download in iTunes 11?
Try this as a work around to an actual download all menu item. Create a new playlist...add your entire library to the playlist. Next to the playlist click the 'Download from iCloud' icon.