What do the various iTunes Match icons in iTunes mean? Enabling iTunes Match adds a new default column to song lists in iTunes that displays several new icons:



What do each of these icons (as well as no icon at all) mean?
Apple's iTunes Match: Understanding the iCloud Status icons KB article explains.



So, your icons in order are:


Available for download
Waiting
Error
Duplicate
Ineligible


If you're having problems, take a look at the Troubleshooting iTunes Match article.