I received a year of "no charge" 20 GB of icloud due to prepaying for several years of mobile me service. It dropped to 5 gb recently so I upgraded. However, I think I upgraded the wrong Apple ID account, as all on the thread are aware that it is easy to open a second one by mistake. I am in a situation now where it appears I have iTunes Match with 95% of my music on one Apple ID, (without the email added to the id name), and 15 gbs of cloud storage for the pictures, numbers/pages documents, home videos, etc for another Apple ID,( exactly the same except the addition of @me.com).
Somehow I was unaware of this as I had selected the same password for both. Recently I was forced to change the password, and i had to have 1 uppercase, and at least 1 number etc. and couldn't use the one I used previously. When I decided to upgrade the cloud storage, I was confused that I kept failing to log in, and checking and double checking that I knew this new password. I tried the old one for kicks, and it took it. It wasn't until I see this thread that I realized
I have two accounts, and as I said, most purchases on one, and the cloud storage upgrade on another.
At least my Apple TV allows me to have both accounts available for imatch, etc.