We are finalizing TP 2.2 implementation and one feature is Test Cases Library. Test Cases library contains general test cases that can be reused in different projects. For example, login functionality is almost the same in all projects as well as login testing. So you may create several test cases for "login user" feature and save them in test case library. Then you may select test cases and copy them into another project. Quite useful stuff.

However, one problem is test cases categorization. You may have 1000+ test cases in library and it is not so simple to find required test cases to copy. There are several options:

1. Add Category property for test case and allow users to add/delete categories. Likely there will be QA lead who manage categories. So people will often ask him "please, add category XYZ".
2. Allow users to describe test cases in free form using tags (so-called folksonomy).

We've decided that solution 2 is more natural and flexible option.

The only problem with tags is that there will be lot of them. So you have to a) highlight tags with high rank and b) provide a way to filter tags. Tags highlighting with font size is a common and good way to show the most frequent tags, while filtering is less common feature. We've implemented tags filter this way. For example, user types "a" and sees only tags that starts on "a", user types "ag" and sees tags starts on "ag" and so on. It is just a lookup filter.

If tags concept will be proven for test cases library we are going to spread it on user stories, bugs and all important content in TargetProcess.