I noticed in my most receant game (beta- most recent update) that if you click on an enemy planet (with no espionage alloted), then leave them selected and bring up you economy screen, that by then adjusting your tax rate it will show how long until that planets next ship is produced. This isn't terribly helpful since it still wouldn't show what ship it is, but it could be used to gauge how much time you have to reach an undefended planet.
I don't know if it is specific to my system either, but I figured I'd let SD know, and theey can look into it.
