Apple thinks iTunes Match is streaming
Once your music is in iCloud, you can stream and store it to any of your devices. Even better, all the music iTunes matches plays back from iCloud at 256-Kbps AAC DRM-free quality — even if your original copy was of lower quality.
Between this and Eddy Cue’s comment that iTunes match would cache or intelligently download your music as you play it, I think its a safe assumption that iTunes match does stream you music to all of your devices. The “cache or intelligently download” means that even though songs are downloaded to your iOS device as you play them when space is running low older songs are removed from your device. I am looking forward to late October when iTunes match is launched.
