Authorized Computers

Hello,

iTunes reports that I have authorized 5 of 5 computers. If I look in the iTunes Store, under Account, in the iCloud section, it says "7 devices are associated with this Apple ID and can download your purchases from iTunes in the Cloud"

If I look at those devices, I only see 2 "computers" listed.

I'd like to know what computers are authorized. For example, is "this MacBook Pro" that I am using right now "Authorized" both now and before I had to reinstall the operating system? Or, does iTunes know it is the same computer? A similar thing might have happened with my primary Windows Desktop, but, I think I deauthorized it before I did the reinstall.

The only other devices of the 7 are iPhones, iPads, and iPods, which if I remember correctly do not count against my 5.

Thanks in advance.