What’s this now?
In addition to updating the inline debugger/preview, Google snuck in a little update to the Advanced Settings section for your tags offering relative control over when a tag will fire in relation to others. Keep in mind that this is all asynchronous, so a series of tags that fire in a specific order do not wait for the previous tag to completely load, so if you have one tag that is dependent on another, you’re still out of luck if you want to fully migrate to GTM. At this rate though, you may not be waiting much longer.
The above updates happened back on July 1st and are detailed on the GTM release notes page.