Test Requests are bug tickets, features or suggestions that have been completed by any developer and are ready for testing.
These requests get verified either by...
1) The original reporter.
2) Active customers, Master/Expert Stencylers or others.
Once they are verified, they go into the Closed category. The purpose of a Test Request is to formally put any new feature or fix through basic testing by someone besides a developer, so that obvious flaws don't make it to production.
Don't be afraid to jump in on a feature or something that interests you. There's no formal protocol around here, and any help is appreciated and will make for a more solid, bug-free end product.