Changing Apple ID and how does it affect iCloud?

Question

Hi,
I had no idea where to put this question since it seems to belong in about 3 different sections, but since it involves my iCloud/Apple/iTunes ID then I suppose this is as good as any place.
I've read a few answers to this question but they don't quite supply all the info I'm trying to find so here goes:
I want to change my Apple ID due to the fact that the email address being used is an old, ISP provided, one that I only tend to use these days for mailing list signups etc. Since, when I created my iCloud account when iOS 5 landed, I (stupidly, before reading that most people seem to advise not doing) chose to associate my iCloud ID to my Apple ID I'm finding all iCloud related notifications are coming from/to my Apple ID email address. I don't really want my shared Calendar changes being sent from/to this account as they can get lost in the deluge of cruft. Obviously in an ideal world I would want to change my Apple ID to my iCloud email address so that the notifications would be coming from there, but obviously this isn't possible yet. I live in hope it may be at some point (foolish I know but hope makes me happy). On that topic, I find it ridiculous that all my other 'verified' email addresses in my Apple ID can be used to change my ID to except the Apple provided me.com one due to that "you cannot use a MobileMe address as an Apple ID since it already is an Apple ID" message. I have never been a MobileMe user. Just iCloud. Maybe when MobileMe goes away this restriction might get lifted......unlikely I suppose but again, I can hope.
First question: could I just delete this iCloud account from my devices (including the Mac) and create a new iCloud account but this time choosing NOT to associate it with my Apple ID? I'd lose my current handy iCloud email address, and have to resync contacts etc but it might be worth it.
Secondly, I tried changing my Apple ID yesterday to another verified email address but lost all iCloud access, due to the Apple ID association I guess. If I deleted the iCloud account on the devices and signed back in with the new Apple ID would that bring me back to where I am now just with a different tied Apple ID? By that I mean full access to current contacts, bookmarks etc etc., without having to resync from anywhere?
Thirdly, which ID is it that controls access to iTunes Match? Apple ID or iCloud ID? Since it's part of iTunes in the Cloud it could be either. On my Mac I'm signed into iTunes with my Apple ID obviously. This gives me access to iTunes Match on the Mac. On my iPhone when I changed my Apple ID and signed into the Store in Settings I still had no access to any iCloud services, including iTunes Match. If I had deleted the account and signed in with the new ID would this have re-enabled iTunes Match? What would happen if the iCloud ID wasn't associated with the iTunes/Apple ID?
Hope most of that made sense. It did in my head.

Answer 1

Apple ID's can be used for anything, a single ID can be used for all your accounts (ie iCloud, iTunes, MAS, Apple community etc), ideally this would be the way forward. So far as iTunes goes you need to continue to use the same ID as you have always used or you will lose access to your previous purchases and your iTunes match subscription.
If you are using a second ID for iCloud, you can continue to do so or use the ID you use for iTunes, but if you choose the later you will need to move all your calendar, contact etc data to the account using the ID you use for iTunes.
When (if) you change which account you use you would delete the account on an iOS device and log back in with the correct details, on a mac you would sign out in the iCloud system preference pane.