If you look at the ServiceNow wiki, you would expect that you need to publish a workflow before you can test.  Well, that is not entirely true and those that have worked with ServiceNow for a while have likely already discovered this is not always the case.  If you are the user that has the workflow checked out, when you execute the workflow, you will see the new (un-published) version execute.  This is very useful as you can make small changes and test without creating hundreds of versions of the workflow (as a result of the publish action).  While very useful, its important to remember that if you are having someone else perform testing of your workflow, you MUST publish the workflow or they WILL NOT see the changes you’ve made.