Ok I am a registered developer with Apple and a technology professional with 14 years of experience in product development of hardware and services like those we are talking about.
On 6 of my test devices... three iPads.. 2 running iOS 7 and one running iOS 6.1.3, as well as 3 iPhones (one of which is running iOS 7 beta 6) and 5 iMacs and a macbook pro and macbook air... the damned lighting bolt indicating services are down are present on all Macs.
on the iDevices, if you wipe the music library and attempt to reconnect to iCloud / iTunes match you will be greeted with an empty library and a brief authentication screen / service negotiation dialogue... apparently something is kicking the clients offline for the matching.
However if an iOS client already has previously matched songs in it's library linked to an online song (i.e. one that is not in the library on the local device) then it will play over the air, even with this current outage.
The desktop client for iTunes will grey out songs previously listed as online and not on the local client, and apparently matching and uploading appears to be non functional, although I haven't done extensive testing.
Right now one iOS client sits with an empty library, same as one MacBook pro, which were working perfectly before yesterday. This does however coincide with a scheduled maintenance period that Apple had announced for its developer services on August 17th... Although things really should be back up and running..
And yes... that service status page is complete utter ********. Apple does not have it tied to any sort of automated monitoring of their system status. Either that or their monitoring is very very poor.
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Incidentally... while I no longer use or even endorse Android hardware / software... I have NEVER had any downtime with Google's online music service. Go figure.