I got the following email from iTunes Store today:
Your subscription for iTunes Match expired on 11/14/12. Your complete music collection and playlists in iCloud are no longer available from your iOS devices, iTunes, or Apple TV. You will still be able to download from iCloud any music you previously purchased on iTunes from the Purchased area of the iTunes Store. You can also sync your music to your iOS devices using iTunes for Mac+PC. To renew your subscription now, open iTunes on your Mac or PC and choose Turn on iTunes Match from the Store menu.
However, when I turn on iTunes Match from the Store menu, it behaves as it always has (as if iTunes Match had never expired), so I have no idea how to actually renew my membership. I've tried turning iTunes Match off and on several times, but it never takes me to any sort of order/renew page. I've also tried signing out/in on iTunes. I definitely want to renew, but for some reason the Auto Renew did not go through (my payment details are fine, as I am able to purchase from the iTunes Store without a hitch).
Any advice? iTunes Match actually seems to be working fine, but I don't want to wait for it to actually die before renewing.