Queues are an awesome tool in JSM projects and now they are buried and awkward to find
In the old UI, when you were in your JSM project, queues were handy and quick on the left nav at the top. Now, they're buried under the Project. You have to go find the project, expand it, find the queue that you want and click on it.
Queues should be added to the items you can add to the top section at the same level as Dashboards and Projects of the new Left Nav via the Customize Sidebar option.