I solved thumbnails bug by deleting all songs in general/usage/ipod, then deleting the folder itunes control through ifiles (it will create a new one) , then reboot (not just respring). (I turned device off and back on again before turning Match back on just to be safe, but not sure it's necessary.) You can go into your Music and see the little spinning wheel constantly working a half second at a time (for each album cover being updated from A to Z).
Close ipod app, transfert your songs to the ipod and the thumbnails should appear. with i Tunes recent update to artwork, this is how I got the new artwork over to my i OS device. Restarting the device wasn't necessary, and, although turning i Tunes Match back on warns you that the music on your device will be replaced, this apparently doesn't apply to music you'd already pulled from Match (as was the case with all the tracks on my i Phone).
Community Q&A Your friend just gave you a disk of some of some of their favourite music and they want you to enjoy it as well.
You rip the disk but now that you play the song there is no album artwork.
This article will show you how to get album artwork.
To force the download of the covers on i OS, make sure you are on wifi and then go to the Music app and tap on . And apply it across all the albums mp3s using the aforementioned tool.
Will experiment with adding my own art and seeing if it pulls through Match, and update here.
If you can see the album art in i Tunes, it will eventually show up in your i OS device when match is turned on.