I just ran across the need to hide the Stay Tuned Updates Coming Soon box from the SharePoint 2013 Time Line. To be candid I have just really started playing around with 2013 and could not find a way out of the box to easily hide the dialog, so naturally I turned to coding like a good nerd should! I had a business requirement that wanted the dialog hidden since it really didn't make sense to have that dialog when the list was simply displaying four tasks for the entire year.
To hide this from the page you can either use a content editor and link to the a script file containing the code below or by adding a code snippet web part to the page. This will hide the dialog from everyone though, so just keep that in mind!
Super short post, but hopefully it was helpful for the particular scenario!